A NULL pointer dereference in Busybox's man applet leads to denial of service when a section name is supplied but no page argument is given

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

  - A NULL pointer dereference in Busybox's man applet leads to denial of service when a section name is     supplied but no page argument is given (CVE-2021-42373)

Note that Nessus relies on the presence of the package as reported by the vendor.

A NULL pointer dereference in Busybox's man applet leads to denial of service when a section name is supplied but no page argument is given.

This plugin only works with Tenable.ot.
Please visit https://www.tenable.com/products/tenable-ot for more information.

The remote host is affected by the vulnerability described in GLSA-202407-17 (BusyBox: Multiple Vulnerabilities)

    Multiple vulnerabilities have been discovered in BusyBox. Please review the CVE identifiers referenced     below for details.

Tenable has extracted the preceding description block directly from the Gentoo Linux security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

There are packages installed that are affected by multiple vulnerabilities referenced in the following CVEs:

  - A NULL pointer dereference in Busybox's man applet leads to denial of service when a section name is
    supplied but no page argument is given (CVE-2021-42373)

  - An incorrect handling of a special element in Busybox's ash applet leads to denial of service when
    processing a crafted shell command, due to the shell mistaking specific characters for reserved
    characters. This may be used for DoS under rare conditions of filtered command input. (CVE-2021-42375)

  - A NULL pointer dereference in Busybox's hush applet leads to denial of service when processing a crafted
    shell command, due to missing validation after a \x03 delimiter character. This may be used for DoS under
    very rare conditions of filtered command input. (CVE-2021-42376)

  - An attacker-controlled pointer free in Busybox's hush applet leads to denial of service and possible code
    execution when processing a crafted shell command, due to the shell mishandling the &&& string. This may
    be used for remote code execution under rare conditions of filtered command input. (CVE-2021-42377)

The remote SUSE Linux SLES12 / SLES_SAP12 host has a package installed that is affected by multiple vulnerabilities as referenced in the SUSE-SU-2022:4253-1 advisory.

    - CVE-2014-9645: Fixed loading of unwanted modules with / (bsc#914660).
    - CVE-2017-16544: Fixed insufficient sanitization of filenames when autocompleting  (bsc#1069412).
    - CVE-2015-9261: Fixed huft_build misuses a pointer, causing segfaults (bsc#1102912).
    - CVE-2016-2147: Fixed out of bounds write (heap) due to integer underflow in udhcpc (bsc#970663).
    - CVE-2016-2148: Fixed heap-based buffer overflow in OPTION_6RD parsing (bsc#970662).
    - CVE-2016-6301: Fixed NTP server denial of service flaw (bsc#991940).
    - CVE-2017-15873: Fixed integer overflow in  get_next_block function in     archival/libarchive/decompress_bunzip2.c (bsc#1064976).
    - CVE-2017-15874: Fixed integer overflow in archival/libarchive/decompress_unlzma (bsc#1064978).
    - CVE-2019-5747: Fixed out of bounds read in udhcp components (bsc#1121428).
    - CVE-2021-42373, CVE-2021-42374, CVE-2021-42375, CVE-2021-42376, CVE-2021-42377, CVE-2021-42378,     CVE-2021-42379, CVE-2021-42380, CVE-2021-42381, CVE-2021-42382, CVE-2021-42383, CVE-2021-42384,     CVE-2021-42385, CVE-2021-42386: v1.34.0 bugfixes (bsc#1192869).
    - CVE-2021-28831: Fixed invalid free or segmentation fault via malformed gzip data (bsc#1184522).
    - CVE-2018-20679: Fixed out of bounds read in udhcp (bsc#1121426).
    - CVE-2018-1000517: Fixed heap-based buffer overflow in the retrieve_file_data() (bsc#1099260).
    - CVE-2011-5325: Fixed tar directory traversal (bsc#951562).
    - CVE-2018-1000500: Fixed missing SSL certificate validation in wget (bsc#1099263).

    - Update to 1.35.0
      - awk: fix printf %%, fix read beyond end of buffer
      - chrt: silence analyzer warning
      - libarchive: remove duplicate forward declaration
      - mount: 'mount -o rw ....' should not fall back to RO mount
      - ps: fix -o pid=PID,args interpreting entire 'PID,args' as header
      - tar: prevent malicious archives with long name sizes causing OOM
      - udhcpc6: fix udhcp_find_option to actually find DHCP6 options
      - xxd: fix -p -r
      - support for new optoins added to basename, cpio, date, find,         mktemp, wget and others

    - Enable fdisk (jsc#CAR-16)

    - Update to 1.34.1:
      * build system: use SOURCE_DATE_EPOCH for timestamp if available
      * many bug fixes and new features
      * touch: make FEATURE_TOUCH_NODEREF unconditional

    - update to 1.33.1:
      * httpd: fix sendfile
      * ash: fix HISTFILE corruptio
      * ash: fix unset variable pattern expansion
      * traceroute: fix option parsing
      * gunzip: fix for archive corruption

    - Update to version 1.33.0
      - many bug fixes and new features

    - Update to version 1.32.1
      - fixes a case where in ash, 'wait' never finishes.

    - prepare usrmerge (bsc#1029961)

    - Enable testsuite and package it for later rerun (for QA, jsc#CAR-15)

    - Update to version 1.31.1:
      - Bug fix release. 1.30.1 has fixes for dc, ash (PS1 expansion         fix), hush, dpkg-deb, telnet and wget.
    - Changes from version 1.31.0:
      - many bugfixes and new features.
    - Add busybox-no-stime.patch: stime() has been deprecated in glibc       2.31 and replaced with clock_settime().

    - update to 1.25.1:
      * fixes for hush, gunzip, ip route, ntpd
    - includes changes from 1.25.0:
      * many added and expanded implementations of command options
    - includes changes from 1.24.2:
      * fixes for build system (static build with glibc fixed),         truncate, gunzip and unzip.

    - Update to version 1.24.1
      * for a full list of changes see http://www.busybox.net/news.html
    - Refresh busybox.install.patch

    - Update to 1.23.2
      * for a full list of changes see http://www.busybox.net/news.html
    - Cleaned up spec file with spec-cleaner
    - Refreshed patches

    - update to 1.22.1:
      Many updates and fixes for most included tools, see       see http://www.busybox.net/news.html

Tenable has extracted the preceding description block directly from the SUSE security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The remote SUSE Linux SLED15 / SLED_SAP15 / SLES15 / SLES_SAP15 / openSUSE 15 host has packages installed that are affected by multiple vulnerabilities as referenced in the SUSE-SU-2022:3959-1 advisory.

    - Enable switch_root       With this change virtme --force-initramfs works as expected.
    - Enable udhcpc

    busybox was updated to 1.35.0

    - Adjust busybox.config for new features in find, date and cpio

    - Annotate CVEs already fixed in upstream, but not mentioned in .changes yet:

    * CVE-2017-16544 (bsc#1069412): Insufficient sanitization of filenames when autocompleting
    * CVE-2015-9261 (bsc#1102912): huft_build misuses a pointer, causing segfaults
    * CVE-2016-2147 (bsc#970663): out of bounds write (heap) due to integer underflow in udhcpc
    * CVE-2016-2148 (bsc#970662): heap-based buffer overflow in OPTION_6RD parsing
    * CVE-2016-6301 (bsc#991940): NTP server denial of service flaw
    * CVE-2017-15873 (bsc#1064976): The get_next_block function in archival/libarchive/decompress_bunzip2.c     has an Integer Overflow
    * CVE-2017-15874 (bsc#1064978): archival/libarchive/decompress_unlzma.c has an Integer Underflow
    * CVE-2019-5747 (bsc#1121428): out of bounds read in udhcp components
    * CVE-2021-42373, CVE-2021-42374, CVE-2021-42375, CVE-2021-42376,       CVE-2021-42377, CVE-2021-42378, CVE-2021-42379, CVE-2021-42380,       CVE-2021-42381, CVE-2021-42382, CVE-2021-42383, CVE-2021-42384,       CVE-2021-42385, CVE-2021-42386 (bsc#1192869) : v1.34.0 bugfixes
    * CVE-2021-28831 (bsc#1184522): invalid free or segmentation fault via malformed gzip data
    * CVE-2018-20679 (bsc#1121426): out of bounds read in udhcp
    * CVE-2018-1000517 (bsc#1099260):  Heap-based buffer overflow in the retrieve_file_data()
    * CVE-2011-5325 (bsc#951562): tar directory traversal
    * CVE-2018-1000500 (bsc#1099263):  wget: Missing SSL certificate validation

Tenable has extracted the preceding description block directly from the SUSE security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The remote SUSE Linux SLES15 host has packages installed that are affected by multiple vulnerabilities as referenced in the SUSE-SU-2022:0135-2 advisory.

    - CVE-2011-5325: Fixed tar directory traversal (bsc#951562).
    - CVE-2015-9261: Fixed segfalts and application crashes in huft_build (bsc#1102912).
    - CVE-2016-2147: Fixed out of bounds write (heap) due to integer underflow in udhcpc (bsc#970663).
    - CVE-2016-2148: Fixed heap-based buffer overflow in OPTION_6RD parsing (bsc#970662).
    - CVE-2016-6301: Fixed NTP server denial of service flaw (bsc#991940).
    - CVE-2017-15873: Fixed integer overflow in get_next_block function in     archival/libarchive/decompress_bunzip2.c (bsc#1064976).
    - CVE-2017-15874: Fixed integer underflow in archival/libarchive/decompress_unlzma.c (bsc#1064978).
    - CVE-2017-16544: Fixed Insufficient sanitization of filenames when autocompleting (bsc#1069412).
    - CVE-2018-1000500 : Fixed missing SSL certificate validation in wget (bsc#1099263).
    - CVE-2018-1000517: Fixed heap-based buffer overflow in the retrieve_file_data() (bsc#1099260).
    - CVE-2018-20679: Fixed out of bounds read in udhcp (bsc#1121426).
    - CVE-2019-5747: Fixed out of bounds read in udhcp components (bsc#1121428).
    - CVE-2021-28831: Fixed invalid free or segmentation fault via malformed gzip data (bsc#1184522).
    - CVE-2021-42373: Fixed NULL pointer dereference in man leading to DoS when a section name is supplied but     no page argument is given (bsc#1192869).
    - CVE-2021-42374: Fixed out-of-bounds heap read in unlzma leading to information leak and DoS when crafted     LZMA-compressed input is decompressed (bsc#1192869).
    - CVE-2021-42375: Fixed incorrect handling of a special element in ash leading to DoS when processing a     crafted shell command, due to the shell mistaking specific characters for reserved characters     (bsc#1192869).
    - CVE-2021-42376: Fixed NULL pointer dereference in hush leading to DoS when processing a crafted shell     command (bsc#1192869).
    - CVE-2021-42377: Fixed attacker-controlled pointer free in hush leading to DoS and possible code     execution when processing a crafted shell command (bsc#1192869).
    - CVE-2021-42378: Fixed use-after-free in awk leading to DoS and possibly code execution when processing a     crafted awk pattern in the getvar_i function (bsc#1192869).
    - CVE-2021-42379: Fixed use-after-free in awk leading to DoS and possibly code execution when processing a     crafted awk pattern in the next_input_file function (bsc#1192869).
    - CVE-2021-42380: Fixed use-after-free in awk leading to DoS and possibly code execution when processing a     crafted awk pattern in the clrvar function (bsc#1192869).
    - CVE-2021-42381: Fixed use-after-free in awk leading to DoS and possibly code execution when processing a     crafted awk pattern in the hash_init function (bsc#1192869).
    - CVE-2021-42382: Fixed use-after-free in awk leading to DoS and possibly code execution when processing a     crafted awk pattern in the getvar_s function (bsc#1192869).
    - CVE-2021-42383: Fixed use-after-free in awk leading to DoS and possibly code execution when processing a     crafted awk pattern in the evaluate function (bsc#1192869).
    - CVE-2021-42384: Fixed use-after-free in awk leading to DoS and possibly code execution when processing a     crafted awk pattern in the handle_special function (bsc#1192869).
    - CVE-2021-42385: Fixed use-after-free in awk leading to DoS and possibly code execution when processing a     crafted awk pattern in the evaluate function (bsc#1192869).
    - CVE-2021-42386: Fixed use-after-free in awk leading to DoS and possibly code execution when processing a     crafted awk pattern in the nvalloc function (bsc#1192869).

Tenable has extracted the preceding description block directly from the SUSE security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The remote SUSE Linux SUSE15 host has packages installed that are affected by multiple vulnerabilities as referenced in the openSUSE-SU-2022:0135-1 advisory.

  - Directory traversal vulnerability in the BusyBox implementation of tar before 1.22.0 v5 allows remote     attackers to point to files outside the current working directory via a symlink. (CVE-2011-5325)

  - huft_build in archival/libarchive/decompress_gunzip.c in BusyBox before 1.27.2 misuses a pointer, causing     segfaults and an application crash during an unzip operation on a specially crafted ZIP file.
    (CVE-2015-9261)

  - Integer overflow in the DHCP client (udhcpc) in BusyBox before 1.25.0 allows remote attackers to cause a     denial of service (crash) via a malformed RFC1035-encoded domain name, which triggers an out-of-bounds     heap write. (CVE-2016-2147)

  - Heap-based buffer overflow in the DHCP client (udhcpc) in BusyBox before 1.25.0 allows remote attackers to     have unspecified impact via vectors involving OPTION_6RD parsing. (CVE-2016-2148)

  - The recv_and_process_client_pkt function in networking/ntpd.c in busybox allows remote attackers to cause     a denial of service (CPU and bandwidth consumption) via a forged NTP packet, which triggers a     communication loop. (CVE-2016-6301)

  - The get_next_block function in archival/libarchive/decompress_bunzip2.c in BusyBox 1.27.2 has an Integer     Overflow that may lead to a write access violation. (CVE-2017-15873)

  - archival/libarchive/decompress_unlzma.c in BusyBox 1.27.2 has an Integer Underflow that leads to a read     access violation. (CVE-2017-15874)

  - In the add_match function in libbb/lineedit.c in BusyBox through 1.27.2, the tab autocomplete feature of     the shell, used to get a list of filenames in a directory, does not sanitize filenames and results in     executing any escape sequence in the terminal. This could potentially result in code execution, arbitrary     file writes, or other attacks. (CVE-2017-16544)

  - Busybox contains a Missing SSL certificate validation vulnerability in The busybox wget applet that can     result in arbitrary code execution. This attack appear to be exploitable via Simply download any file over     HTTPS using busybox wget https://compromised-domain.com/important-file. (CVE-2018-1000500)

  - BusyBox project BusyBox wget version prior to commit 8e2174e9bd836e53c8b9c6e00d1bc6e2a718686e contains a     Buffer Overflow vulnerability in Busybox wget that can result in heap buffer overflow. This attack appear     to be exploitable via network connectivity. This vulnerability appears to have been fixed in after commit     8e2174e9bd836e53c8b9c6e00d1bc6e2a718686e. (CVE-2018-1000517)

  - An issue was discovered in BusyBox before 1.30.0. An out of bounds read in udhcp components (consumed by     the DHCP server, client, and relay) allows a remote attacker to leak sensitive information from the stack     by sending a crafted DHCP message. This is related to verification in udhcp_get_option() in     networking/udhcp/common.c that 4-byte options are indeed 4 bytes. (CVE-2018-20679)

  - An issue was discovered in BusyBox through 1.30.0. An out of bounds read in udhcp components (consumed by     the DHCP server, client, and/or relay) might allow a remote attacker to leak sensitive information from     the stack by sending a crafted DHCP message. This is related to assurance of a 4-byte length when decoding     DHCP_SUBNET. NOTE: this issue exists because of an incomplete fix for CVE-2018-20679. (CVE-2019-5747)

  - decompress_gunzip.c in BusyBox through 1.32.1 mishandles the error bit on the huft_build result pointer,     with a resultant invalid free or segmentation fault, via malformed gzip data. (CVE-2021-28831)

  - A NULL pointer dereference in Busybox's man applet leads to denial of service when a section name is     supplied but no page argument is given (CVE-2021-42373)

  - An out-of-bounds heap read in Busybox's unlzma applet leads to information leak and denial of service when     crafted LZMA-compressed input is decompressed. This can be triggered by any applet/format that     (CVE-2021-42374)

  - An incorrect handling of a special element in Busybox's ash applet leads to denial of service when     processing a crafted shell command, due to the shell mistaking specific characters for reserved     characters. This may be used for DoS under rare conditions of filtered command input. (CVE-2021-42375)

  - A NULL pointer dereference in Busybox's hush applet leads to denial of service when processing a crafted     shell command, due to missing validation after a \x03 delimiter character. This may be used for DoS under     very rare conditions of filtered command input. (CVE-2021-42376)

  - An attacker-controlled pointer free in Busybox's hush applet leads to denial of service and possible code     execution when processing a crafted shell command, due to the shell mishandling the &&& string. This may     be used for remote code execution under rare conditions of filtered command input. (CVE-2021-42377)

  - A use-after-free in Busybox's awk applet leads to denial of service and possibly code execution when     processing a crafted awk pattern in the getvar_i function (CVE-2021-42378)

  - A use-after-free in Busybox's awk applet leads to denial of service and possibly code execution when     processing a crafted awk pattern in the next_input_file function (CVE-2021-42379)

  - A use-after-free in Busybox's awk applet leads to denial of service and possibly code execution when     processing a crafted awk pattern in the clrvar function (CVE-2021-42380)

  - A use-after-free in Busybox's awk applet leads to denial of service and possibly code execution when     processing a crafted awk pattern in the hash_init function (CVE-2021-42381)

  - A use-after-free in Busybox's awk applet leads to denial of service and possibly code execution when     processing a crafted awk pattern in the getvar_s function (CVE-2021-42382)

  - A use-after-free in Busybox's awk applet leads to denial of service and possibly code execution when     processing a crafted awk pattern in the evaluate function (CVE-2021-42383, CVE-2021-42385)

  - A use-after-free in Busybox's awk applet leads to denial of service and possibly code execution when     processing a crafted awk pattern in the handle_special function (CVE-2021-42384)

  - A use-after-free in Busybox's awk applet leads to denial of service and possibly code execution when     processing a crafted awk pattern in the nvalloc function (CVE-2021-42386)

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

The remote SUSE Linux SLED15 / SLED_SAP15 / SLES15 / SLES_SAP15 host has packages installed that are affected by multiple vulnerabilities as referenced in the SUSE-SU-2022:0135-1 advisory.

    - CVE-2011-5325: Fixed tar directory traversal (bsc#951562).
    - CVE-2015-9261: Fixed segfalts and application crashes in huft_build (bsc#1102912).
    - CVE-2016-2147: Fixed out of bounds write (heap) due to integer underflow in udhcpc (bsc#970663).
    - CVE-2016-2148: Fixed heap-based buffer overflow in OPTION_6RD parsing (bsc#970662).
    - CVE-2016-6301: Fixed NTP server denial of service flaw (bsc#991940).
    - CVE-2017-15873: Fixed integer overflow in get_next_block function in     archival/libarchive/decompress_bunzip2.c (bsc#1064976).
    - CVE-2017-15874: Fixed integer underflow in archival/libarchive/decompress_unlzma.c (bsc#1064978).
    - CVE-2017-16544: Fixed Insufficient sanitization of filenames when autocompleting (bsc#1069412).
    - CVE-2018-1000500 : Fixed missing SSL certificate validation in wget (bsc#1099263).
    - CVE-2018-1000517: Fixed heap-based buffer overflow in the retrieve_file_data() (bsc#1099260).
    - CVE-2018-20679: Fixed out of bounds read in udhcp (bsc#1121426).
    - CVE-2019-5747: Fixed out of bounds read in udhcp components (bsc#1121428).
    - CVE-2021-28831: Fixed invalid free or segmentation fault via malformed gzip data (bsc#1184522).
    - CVE-2021-42373: Fixed NULL pointer dereference in man leading to DoS when a section name is supplied but     no page argument is given (bsc#1192869).
    - CVE-2021-42374: Fixed out-of-bounds heap read in unlzma leading to information leak and DoS when crafted     LZMA-compressed input is decompressed (bsc#1192869).
    - CVE-2021-42375: Fixed incorrect handling of a special element in ash leading to DoS when processing a     crafted shell command, due to the shell mistaking specific characters for reserved characters     (bsc#1192869).
    - CVE-2021-42376: Fixed NULL pointer dereference in hush leading to DoS when processing a crafted shell     command (bsc#1192869).
    - CVE-2021-42377: Fixed attacker-controlled pointer free in hush leading to DoS and possible code     execution when processing a crafted shell command (bsc#1192869).
    - CVE-2021-42378: Fixed use-after-free in awk leading to DoS and possibly code execution when processing a     crafted awk pattern in the getvar_i function (bsc#1192869).
    - CVE-2021-42379: Fixed use-after-free in awk leading to DoS and possibly code execution when processing a     crafted awk pattern in the next_input_file function (bsc#1192869).
    - CVE-2021-42380: Fixed use-after-free in awk leading to DoS and possibly code execution when processing a     crafted awk pattern in the clrvar function (bsc#1192869).
    - CVE-2021-42381: Fixed use-after-free in awk leading to DoS and possibly code execution when processing a     crafted awk pattern in the hash_init function (bsc#1192869).
    - CVE-2021-42382: Fixed use-after-free in awk leading to DoS and possibly code execution when processing a     crafted awk pattern in the getvar_s function (bsc#1192869).
    - CVE-2021-42383: Fixed use-after-free in awk leading to DoS and possibly code execution when processing a     crafted awk pattern in the evaluate function (bsc#1192869).
    - CVE-2021-42384: Fixed use-after-free in awk leading to DoS and possibly code execution when processing a     crafted awk pattern in the handle_special function (bsc#1192869).
    - CVE-2021-42385: Fixed use-after-free in awk leading to DoS and possibly code execution when processing a     crafted awk pattern in the evaluate function (bsc#1192869).
    - CVE-2021-42386: Fixed use-after-free in awk leading to DoS and possibly code execution when processing a     crafted awk pattern in the nvalloc function (bsc#1192869).

Tenable has extracted the preceding description block directly from the SUSE security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

ID	Name	Product	Family	Severity
224133	Linux Distros Unpatched Vulnerability : CVE-2021-42373	Nessus	Misc.	medium
503034	Siemens SIMATIC S7-1500 TM MFP BIOS NULL Pointer Dereference (CVE-2021-42373)	Tenable OT Security	Tenable.ot	medium
201913	GLSA-202407-17 : BusyBox: Multiple Vulnerabilities	Nessus	Gentoo Local Security Checks	critical
403725	Alpine: busybox: security update to 0	Tenable Cloud Security	Alpine Linux Local Security Checks	critical
403725	Alpine: busybox: security update to 0	Tenable Self-Hosted Container Security	Alpine Linux Local Security Checks	critical
168240	SUSE SLES12 Security Update : busybox (SUSE-SU-2022:4253-1)	Nessus	SuSE Local Security Checks	critical
167330	SUSE SLED15 / SLES15 / openSUSE 15 Security Update : busybox (SUSE-SU-2022:3959-1)	Nessus	SuSE Local Security Checks	critical
158060	SUSE SLES15 Security Update : busybox (SUSE-SU-2022:0135-2)	Nessus	SuSE Local Security Checks	critical
156938	openSUSE 15 Security Update : busybox (openSUSE-SU-2022:0135-1)	Nessus	SuSE Local Security Checks	critical
156924	SUSE SLED15 / SLES15 Security Update : busybox (SUSE-SU-2022:0135-1)	Nessus	SuSE Local Security Checks	critical

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CVE-2021-42373

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