Double-free vulnerability in the FTP-kerberos code in cURL 7.52.0 to 7.65.3.

The remote Oracle Linux 8 host has packages installed that are affected by multiple vulnerabilities as referenced in the ELSA-2020-1792 advisory.

  - Heap buffer overflow in the TFTP protocol handler in cURL 7.19.4 to 7.65.3. (CVE-2019-5482)

  - A heap buffer overflow in the TFTP receiving code allows for DoS or arbitrary code execution in libcurl     versions 7.19.4 through 7.64.1. (CVE-2019-5436)

  - Double-free vulnerability in the FTP-kerberos code in cURL 7.52.0 to 7.65.3. (CVE-2019-5481)

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

The remote CentOS Linux 8 host has packages installed that are affected by multiple vulnerabilities as referenced in the CESA-2020:1792 advisory.

  - curl: TFTP receive heap buffer overflow in tftp_receive_packet() function (CVE-2019-5436)

  - curl: double free due to subsequent call of realloc() (CVE-2019-5481)

  - curl: heap buffer overflow in function tftp_receive_packet() (CVE-2019-5482)

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

The remote Redhat Enterprise Linux 8 host has packages installed that are affected by multiple vulnerabilities as referenced in the RHSA-2020:1792 advisory.

  - curl: TFTP receive heap buffer overflow in tftp_receive_packet() function (CVE-2019-5436)

  - curl: double free due to subsequent call of realloc() (CVE-2019-5481)

  - curl: heap buffer overflow in function tftp_receive_packet() (CVE-2019-5482)

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

The remote host is affected by the vulnerability described in GLSA-202003-29 (cURL: Multiple vulnerabilities)

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

    A remote attacker could possibly execute arbitrary code with the       privileges of the process or cause a Denial of Service condition.
  Workaround :

    There is no known workaround at this time.

Multiple vulnerabilities were discovered in cURL, an URL transfer library.

  - CVE-2019-5436     A heap buffer overflow in the TFTP receiving code was     discovered, which could allow DoS or arbitrary code     execution. This only affects the oldstable distribution     (stretch).

  - CVE-2019-5481     Thomas Vegas discovered a double-free in the FTP-KRB     code, triggered by a malicious server sending a very     large data block.

  - CVE-2019-5482     Thomas Vegas discovered a heap buffer overflow that     could be triggered when a small non-default TFTP     blocksize is used.

The remote Redhat Enterprise Linux 6 / 7 host has packages installed that are affected by multiple vulnerabilities as referenced in the RHSA-2020:0250 advisory.

  - httpd: URL normalization inconsistency (CVE-2019-0220)

  - curl: double free due to subsequent call of realloc() (CVE-2019-5481)

  - curl: heap buffer overflow in function tftp_receive_packet() (CVE-2019-5482)

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

According to the versions of the curl packages installed, the EulerOS Virtualization for ARM 64 installation on the remote host is affected by the following vulnerabilities :

  - curl is a command line tool for transferring data with     URL syntax, supporting FTP, FTPS, HTTP, HTTPS, SCP,     SFTP, TFTP, TELNET, DICT, LDAP, LDAPS, FILE, IMAP,     SMTP, POP3 and RTSP. curl supports SSL certificates,     HTTP POST, HTTP PUT, FTP uploading, HTTP form based     upload, proxies, cookies, user+password authentication     (Basic, Digest, NTLM, Negotiate, kerberos...), file     transfer resume, proxy tunneling and a busload of other     useful tricks. Security Fix(es):Heap buffer overflow in     the TFTP protocol handler in cURL 7.19.4 to     7.65.3.(CVE-2019-5482)This vulnerability has been     modified since it was last analyzed by the NVD. It is     awaiting reanalysis which may result in further changes     to the information provided.(CVE-2019-5481)

Note that Tenable Network Security has extracted the preceding description block directly from the EulerOS security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

According to the versions of the curl packages installed, the EulerOS installation on the remote host is affected by the following vulnerabilities :

  - Double-free vulnerability in the FTP-kerberos code in     cURL 7.52.0 to 7.65.3.(CVE-2019-5481)

  - Heap buffer overflow in the TFTP protocol handler in     cURL 7.19.4 to 7.65.3.(CVE-2019-5482)

Note that Tenable Network Security has extracted the preceding description block directly from the EulerOS security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

Double-free vulnerability in the FTP-kerberos code in cURL 7.52.0 to 7.65.3.(CVE-2019-5481)

Heap buffer overflow in the TFTP protocol handler in cURL 7.19.4 to 7.65.3.(CVE-2019-5482)

An update of the curl package has been released.

- double free due to subsequent call of realloc()     (CVE-2019-5481)

  - fix heap buffer overflow in function     tftp_receive_packet() (CVE-2019-5482)

----

  - avoid reporting spurious error in the HTTP2 framing     layer (#1690971)

Note that Tenable Network Security has extracted the preceding description block directly from the Fedora update system website.
Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

Heap buffer overflow in the TFTP protocol handler in cURL 7.19.4 to 7.65.3. (CVE-2019-5482)

Double-free vulnerability in the FTP-kerberos code in cURL 7.52.0 to 7.65.3. (CVE-2019-5481)

- double free due to subsequent call of realloc()     (CVE-2019-5481)

  - fix heap buffer overflow in function     tftp_receive_packet() (CVE-2019-5482)

Note that Tenable Network Security has extracted the preceding description block directly from the Fedora update system website.
Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

This update for curl fixes the following issues :

Security issues fixed :

  - CVE-2019-5481: Fixed FTP-KRB double-free during kerberos     FTP data transfer (bsc#1149495).

  - CVE-2019-5482: Fixed TFTP small blocksize heap buffer     overflow (bsc#1149496).

This update was imported from the SUSE:SLE-15:Update update project.

This update for curl fixes the following issues :

Security issues fixed :

CVE-2019-5481: Fixed a double-free during kerberos FTP data transfer.
(bsc#1149495)

CVE-2019-5482: Fixed a TFTP small block size heap buffer overflow (bsc#1149496).

Note that Tenable Network Security has extracted the preceding description block directly from the SUSE security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

This update for curl fixes the following issues :

Security issues fixed :

CVE-2019-5481: Fixed FTP-KRB double-free during kerberos FTP data transfer (bsc#1149495).

CVE-2019-5482: Fixed TFTP small blocksize heap buffer overflow (bsc#1149496).

Note that Tenable Network Security has extracted the preceding description block directly from the SUSE security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

curl security problems :

CVE-2019-5481: FTP-KRB double-free

libcurl can be told to use kerberos over FTP to a server, as set with the CURLOPT_KRBLEVEL option.

During such kerberos FTP data transfer, the server sends data to curl in blocks with the 32 bit size of each block first and then that amount of data immediately following.

A malicious or just broken server can claim to send a very large block and if by doing that it makes curl's subsequent call to realloc() to fail, curl would then misbehave in the exit path and double-free the memory.

In practical terms, an up to 4 GB memory area may very well be fine to allocate on a modern 64 bit system but on 32 bit systems it will fail.

Kerberos FTP is a rarely used protocol with curl. Also, Kerberos authentication is usually only attempted and used with servers that the client has a previous association with.

CVE-2019-5482: TFTP small blocksize heap buffer overflow

libcurl contains a heap buffer overflow in the function (tftp_receive_packet()) that receives data from a TFTP server. It can call recvfrom() with the default size for the buffer rather than with the size that was used to allocate it. Thus, the content that might overwrite the heap memory is controlled by the server.

This flaw is only triggered if the TFTP server sends an OACK without the BLKSIZE option, when a BLKSIZE smaller than 512 bytes was requested by the TFTP client. OACK is a TFTP extension and is not used by all TFTP servers.

Users choosing a smaller block size than default should be rare as the primary use case for changing the size is to make it larger.

It is rare for users to use TFTP across the Internet. It is most commonly used within local networks. TFTP as a protocol is always inherently insecure.

This issue was introduced by the add of the TFTP BLKSIZE option handling. It was previously incompletely fixed by an almost identical issue called CVE-2019-5436.

Thomas Vegas discovered that curl incorrectly handled memory when using Kerberos over FTP. A remote attacker could use this issue to crash curl, resulting in a denial of service. (CVE-2019-5481)

Thomas Vegas discovered that curl incorrectly handled memory during TFTP transfers. A remote attacker could use this issue to crash curl, resulting in a denial of service, or possibly execute arbitrary code.
(CVE-2019-5482).

Note that Tenable Network Security has extracted the preceding description block directly from the Ubuntu security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

New curl packages are available for Slackware 14.0, 14.1, 14.2, and
-current to fix security issues.

ID	Name	Product	Family	Severity
180880	Oracle Linux 8 : curl (ELSA-2020-1792)	Nessus	Oracle Linux Local Security Checks	critical
146018	CentOS 8 : curl (CESA-2020:1792)	Nessus	CentOS Local Security Checks	critical
136051	RHEL 8 : curl (RHSA-2020:1792)	Nessus	Red Hat Local Security Checks	critical
134606	GLSA-202003-29 : cURL: Multiple vulnerabilities	Nessus	Gentoo Local Security Checks	critical
133968	Debian DSA-4633-1 : curl - security update	Nessus	Debian Local Security Checks	critical
133333	RHEL 6 / 7 : Red Hat JBoss Core Services Apache HTTP Server 2.4.37 SP1 Security Update (Low) (RHSA-2020:0250)	Nessus	Red Hat Local Security Checks	critical
132824	EulerOS Virtualization for ARM 64 3.0.5.0 : curl (EulerOS-SA-2020-1070)	Nessus	Huawei Local Security Checks	critical
130810	EulerOS 2.0 SP8 : curl (EulerOS-SA-2019-2101)	Nessus	Huawei Local Security Checks	critical
130236	Amazon Linux 2 : curl (ALAS-2019-1340)	Nessus	Amazon Linux Local Security Checks	critical
130111	Photon OS 3.0: Curl PHSA-2019-3.0-0032	Nessus	PhotonOS Local Security Checks	critical
129689	Photon OS 2.0: Curl PHSA-2019-2.0-0177	Nessus	PhotonOS Local Security Checks	critical
129626	Fedora 31 : curl (2019-6d7f6fa2c8)	Nessus	Fedora Local Security Checks	critical
129564	Amazon Linux AMI : curl (ALAS-2019-1294)	Nessus	Amazon Linux Local Security Checks	critical
129424	Fedora 29 : curl (2019-f2a520135e)	Nessus	Fedora Local Security Checks	critical
129338	openSUSE Security Update : curl (openSUSE-2019-2169)	Nessus	SuSE Local Security Checks	critical
128987	openSUSE Security Update : curl (openSUSE-2019-2149)	Nessus	SuSE Local Security Checks	critical
128978	Fedora 30 : curl (2019-9e6357d82f)	Nessus	Fedora Local Security Checks	critical
128966	SUSE SLED12 / SLES12 Security Update : curl (SUSE-SU-2019:2381-1)	Nessus	SuSE Local Security Checks	critical
128873	SUSE SLED15 / SLES15 Security Update : curl (SUSE-SU-2019:2373-1)	Nessus	SuSE Local Security Checks	critical
128795	FreeBSD : curl -- multiple vulnerabilities (9fb4e57b-d65a-11e9-8a5f-e5c82b486287)	Nessus	FreeBSD Local Security Checks	critical
128754	Ubuntu 16.04 LTS / 18.04 LTS : curl vulnerabilities (USN-4129-1)	Nessus	Ubuntu Local Security Checks	critical
128749	Slackware 14.0 / 14.1 / 14.2 / current : curl (SSA:2019-254-01)	Nessus	Slackware Local Security Checks	critical

Detections

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CVE-2019-5481

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