openSUSE Security Update : exim (openSUSE-2021-677) (Stack Clash)

critical Nessus Plugin ID 149614
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Synopsis

The remote openSUSE host is missing a security update.

Description

This update for exim fixes the following issues :

Exim was updated to exim-4.94.2

security update (boo#1185631)

- CVE-2020-28007: Link attack in Exim's log directory

- CVE-2020-28008: Assorted attacks in Exim's spool directory

- CVE-2020-28014: Arbitrary PID file creation

- CVE-2020-28011: Heap buffer overflow in queue_run()

- CVE-2020-28010: Heap out-of-bounds write in main()

- CVE-2020-28013: Heap buffer overflow in parse_fix_phrase()

- CVE-2020-28016: Heap out-of-bounds write in parse_fix_phrase()

- CVE-2020-28015: New-line injection into spool header file (local)

- CVE-2020-28012: Missing close-on-exec flag for privileged pipe

- CVE-2020-28009: Integer overflow in get_stdinput()

- CVE-2020-28017: Integer overflow in receive_add_recipient()

- CVE-2020-28020: Integer overflow in receive_msg()

- CVE-2020-28023: Out-of-bounds read in smtp_setup_msg()

- CVE-2020-28021: New-line injection into spool header file (remote)

- CVE-2020-28022: Heap out-of-bounds read and write in extract_option()

- CVE-2020-28026: Line truncation and injection in spool_read_header()

- CVE-2020-28019: Failure to reset function pointer after BDAT error

- CVE-2020-28024: Heap buffer underflow in smtp_ungetc()

- CVE-2020-28018: Use-after-free in tls-openssl.c

- CVE-2020-28025: Heap out-of-bounds read in pdkim_finish_bodyhash()

update to exim-4.94.1

- Fix security issue in BDAT state confusion. Ensure we reset known-good where we know we need to not be reading BDAT data, as a general case fix, and move the places where we switch to BDAT mode until after various protocol state checks. Fixes CVE-2020-BDATA reported by Qualys.

- Fix security issue in SMTP verb option parsing (CVE-2020-EXOPT)

- Fix security issue with too many recipients on a message (to remove a known security problem if someone does set recipients_max to unlimited, or if local additions add to the recipient list). Fixes CVE-2020-RCPTL reported by Qualys.

- Fix CVE-2020-28016 (PFPZA): Heap out-of-bounds write in parse_fix_phrase()

- Fix security issue CVE-2020-PFPSN and guard against cmdline invoker providing a particularly obnoxious sender full name.

- Fix Linux security issue CVE-2020-SLCWD and guard against PATH_MAX better.

- bring back missing exim_db.8 manual page (fixes boo#1173693)

- bring in changes from current +fixes (lots of taint check fixes)

- Bug 1329: Fix format of Maildir-format filenames to match other mail- related applications. Previously an 'H' was used where available info says that 'M' should be, so change to match.

- Bug 2587: Fix pam expansion condition. Tainted values are commonly used as arguments, so an implementation trying to copy these into a local buffer was taking a taint-enforcement trap. Fix by using dynamically created buffers.

- Bug 2586: Fix listcount expansion operator. Using tainted arguments is reasonable, eg. to count headers.
Fix by using dynamically created buffers rather than a local. Do similar fixes for ACL actions 'dcc', 'log_reject_target', 'malware' and 'spam'; the arguments are expanded so could be handling tainted values.

- Bug 2590: Fix -bi (newaliases). A previous code rearrangement had broken the (no-op) support for this sendmail command. Restore it to doing nothing, silently, and returning good status.

- update to exim 4.94

- some transports now refuse to use tainted data in constructing their delivery location this WILL BREAK configurations which are not updated accordingly. In particular: any Transport use of $local_user which has been relying upon check_local_user far away in the Router to make it safe, should be updated to replace $local_user with $local_part_data.

- Attempting to remove, in router or transport, a header name that ends with an asterisk (which is a standards-legal name) will now result in all headers named starting with the string before the asterisk being removed.

- switch pretrans to use lua (fixes boo#1171877)



- bring changes from current in +fixes branch (patch-exim-fixes-ee83de04d3087efaf808d1f2235a988275c2ee 94)

- fixes CVE-2020-12783 (boo#1171490)

- Regard command-line recipients as tainted.

- Bug 2489: Fix crash in the 'pam' expansion condition.

- Use tainted buffers for the transport smtp context.

- Bug 2493: Harden ARC verify against Outlook, which has been seen to mix the ordering of its ARC headers. This caused a crash.

- Bug 2492: Use tainted memory for retry record when needed. Previously when a new record was being constructed with information from the peer, a trap was taken.

- Bug 2494: Unset the default for dmarc_tld_file.

- Fix an uninitialised flag in early-pipelining.
Previously connections could, depending on the platform, hang at the STARTTLS response.

- Bug 2498: Reset a counter used for ARC verify before handling another message on a connection. Previously if one message had ARC headers and the following one did not, a crash could result when adding an Authentication-Results: header.

- Bug 2500: Rewind some of the common-coding in string handling between the Exim main code and Exim-related utities.

- Fix the variables set by the gsasl authenticator.

- Bug 2507: Modules: on handling a dynamic-module (lookups) open failure, only retrieve the errormessage once.

- Bug 2501: Fix init call in the heimdal authenticator.
Previously it adjusted the size of a major service buffer; this failed because the buffer was in use at the time. Change to a compile-time increase in the buffer size, when this authenticator is compiled into exim.

- update to exim 4.93.0.4 (+fixes release)

- Avoid costly startup code when not strictly needed. This reduces time for some exim process initialisations. It does mean that the logging of TLS configuration problems is only done for the daemon startup.

- Early-pipelining support code is now included unless disabled in Makefile.

- DKIM verification defaults no long accept sha1 hashes, to conform to RFC 8301. They can still be enabled, using the dkim_verify_hashes main option.

- Support CHUNKING from an smtp transport using a transport_filter, when DKIM signing is being done.
Previously a transport_filter would always disable CHUNKING, falling back to traditional DATA.

- Regard command-line receipients as tainted.

- Bug 340: Remove the daemon pid file on exit, whe due to SIGTERM.

- Bug 2489: Fix crash in the 'pam' expansion condition. It seems that the PAM library frees one of the arguments given to it, despite the documentation. Therefore a plain malloc must be used.

- Bug 2491: Use tainted buffers for the transport smtp context. Previously on-stack buffers were used, resulting in a taint trap when DSN information copied from a received message was written into the buffer.

- Bug 2493: Harden ARC verify against Outlook, whick has been seen to mix the ordering of its ARC headers. This caused a crash.

- Bug 2492: Use tainted memory for retry record when needed. Previously when a new record was being constructed with information from the peer, a trap was taken.

- Bug 2494: Unset the default for dmarc_tld_file.
Previously a naiive installation would get error messages from DMARC verify, when it hit the nonexistent file indicated by the default. Distros wanting DMARC enabled should both provide the file and set the option.
Also enforce no DMARC verification for command-line sourced messages.

- Fix an uninitialised flag in early-pipelining.
Previously connections could, depending on the platform, hang at the STARTTLS response.

- Bug 2498: Reset a counter used for ARC verify before handling another message on a connection. Previously if one message had ARC headers and the following one did not, a crash could result when adding an Authentication-Results: header.

- Bug 2500: Rewind some of the common-coding in string handling between the Exim main code and Exim-related utities. The introduction of taint tracking also did many adjustments to string handling. Since then, eximon frequently terminated with an assert failure.

- When PIPELINING, synch after every hundred or so RCPT commands sent and check for 452 responses. This slightly helps the inefficieny of doing a large alias-expansion into a recipient-limited target. The max_rcpt transport option still applies (and at the current default, will override the new feature). The check is done for either cause of synch, and forces a fast-retry of all 452'd recipients using a new MAIL FROM on the same connection.
The new facility is not tunable at this time.

- Fix the variables set by the gsasl authenticator.
Previously a pointer to library live data was being used, so the results became garbage. Make copies while it is still usable.

- Logging: when the deliver_time selector ise set, include the DT= field on delivery deferred (==) and failed (**) lines (if a delivery was attemtped). Previously it was only on completion (=>) lines.

- Authentication: the gsasl driver not provides the $authN variables in time for the expansion of the server_scram_iter and server_scram_salt options.

spec file cleanup to make update work

- add docdir to spec

- update to exim 4.93

- SUPPORT_DMARC replaces EXPERIMENTAL_DMARC

- DISABLE_TLS replaces SUPPORT_TLS

- Bump the version for the local_scan API.

- smtp transport option hosts_try_fastopen defaults to '*'.

- DNSSec is requested (not required) for all queries.
(This seemes to ask for trouble if your resolver is a systemd-resolved.)

- Generic router option retry_use_local_part defaults to 'true' under specific pre-conditions.

- Introduce a tainting mechanism for values read from untrusted sources.

- Use longer file names for temporary spool files (this avoids name conflicts with spool on a shared file system).

- Use dsn_from main config option (was ignored previously).

- update to exim 4.92.3

- CVE-2019-16928: fix against Heap-based buffer overflow in string_vformat, remote code execution seems to be possible

- update to exim 4.92.2

- CVE-2019-15846: fix against remote attackers executing arbitrary code as root via a trailing backslash

- update to exim 4.92.1

- CVE-2019-13917: Fixed an issue with $(sort) expansion which could allow remote attackers to execute other programs with root privileges (boo#1142207)

- spec file cleanup

- fix DANE inclusion guard condition

- re-enable i18n and remove misleading comment

- EXPERIMENTAL_SPF is now SUPPORT_SPF

- DANE is now SUPPORT_DANE

- update to exim 4.92

- $(l_header:<name>) expansion

- $(readsocket) now supports TLS

- 'utf8_downconvert' option (if built with SUPPORT_I18N)

- 'pipelining' log_selector

- JSON variants for $(extract ) expansion

- 'noutf8' debug option

- TCP Fast Open support on MacOS

- CVE-2019-10149: Fixed a Remote Command Execution (boo#1136587)

- add workaround patch for compile time error on missing printf format annotation (gnu_printf.patch)

- update to 4.91

- DEFER rather than ERROR on redis cluster MOVED response.

- Catch and remove uninitialized value warning in exiqsumm

- Disallow '/' characters in queue names specified for the 'queue=' ACL modifier. This matches the restriction on the commandline.

- Fix pgsql lookup for multiple result-tuples with a single column. Previously only the last row was returned.

- Bug 2217: Tighten up the parsing of DKIM signature headers.

- Bug 2215: Fix crash associated with dnsdb lookup done from DKIM ACL.

- Fix issue with continued-connections when the DNS shifts unreliably.

- Bug 2214: Fix SMTP responses resulting from non-accept result of MIME ACL.

- The 'support for' informational output now, which built with Content Scanning support, has a line for the malware scanner interfaces compiled in. Interface can be individually included or not at build time.

- The 'aveserver', 'kavdaemon' and 'mksd' interfaces are now not included by the template makefile 'src/EDITME'.
The 'STREAM' support for an older ClamAV interface method is removed.

- Bug 2223: Fix mysql lookup returns for the no-data case (when the number of rows affected is given instead).

- The runtime Berkeley DB library version is now additionally output by 'exim -d -bV'. Previously only the compile-time version was shown.

- Bug 2230: Fix cutthrough routing for nonfirst messages in an initiating SMTP connection.

- Bug 2229: Fix cutthrough routing for nonstandard port numbers defined by routers.

- Bug 2174: A timeout on connect for a callout was also erroneously seen as a timeout on read on a GnuTLS initiating connection, resulting in the initiating connection being dropped.

- Relax results from ACL control request to enable cutthrough, in unsupported situations, from error to silently (except under debug) ignoring.

- Fix Buffer overflow in base64d() (CVE-2018-6789)

- Fix bug in DKIM verify: a buffer overflow could corrupt the malloc metadata, resulting in a crash in free().

- Fix broken Heimdal GSSAPI authenticator integration.

- Bug 2113: Fix conversation closedown with the Avast malware scanner.

- Bug 2239: Enforce non-usability of control=utf8_downconvert in the mail ACL.

- Speed up macro lookups during configuration file read, by skipping non- macro text after a replacement (previously it was only once per line) and by skipping builtin macros when searching for an uppercase lead character.

- DANE support moved from Experimental to mainline. The Makefile control for the build is renamed.

- Fix memory leak during multi-message connections using STARTTLS.

- Bug 2236: When a DKIM verification result is overridden by ACL, DMARC reported the original. Fix to report (as far as possible) the ACL result replacing the original.

- Fix memory leak during multi-message connections using STARTTLS under OpenSSL

- Bug 2242: Fix exim_dbmbuild to permit directoryless filenames.

- Fix utf8_downconvert propagation through a redirect router.

- Bug 2253: For logging delivery lines under PRDR, append the overall DATA response info to the (existing) per-recipient response info for the 'C=' log element.

- Bug 2251: Fix ldap lookups that return a single attribute having zero- length value.

- Support Avast multiline protocol, this allows passing flags to newer versions of the scanner.

- Ensure that variables possibly set during message acceptance are marked dead before release of memory in the daemon loop.

- Bug 2250: Fix a longstanding bug in heavily-pipelined SMTP input (such as a multi-recipient message from a mailinglist manager).

- The (EXPERIMENTAL_DMARC) variable $dmarc_ar_header is withdrawn, being replaced by the $(authresults ) expansion.

- Bug 2257: Fix pipe transport to not use a socket-only syscall.

- Set a handler for SIGTERM and call exit(3) if running as PID 1. This allows proper process termination in container environments.

- Bug 2258: Fix spool_wireformat in combination with LMTP transport. Previously the 'final dot' had a newline after it; ensure it is CR,LF.

- SPF: remove support for the 'spf' ACL condition outcome values 'err_temp' and 'err_perm', deprecated since 4.83 when the RFC-defined words ' temperror' and 'permerror' were introduced.

- Re-introduce enforcement of no cutthrough delivery on transports having transport-filters or DKIM-signing.

- Cutthrough: for a final-dot response timeout (and nonunderstood responses) in defer=pass mode supply a 450 to the initiator. Previously the message would be spooled.

- DANE: add dane_require_tls_ciphers SMTP Transport option; if unset, tls_require_ciphers is used as before.

- Malware Avast: Better match the Avast multiline protocol.

- Fix reinitialisation of DKIM logging variable between messages.

- Bug 2255: Revert the disable of the OpenSSL session caching.

- Add util/renew-opendmarc-tlds.sh script for safe renewal of public suffix list.

- DKIM: accept Ed25519 pubkeys in SubjectPublicKeyInfo-wrapped form, since the IETF WG has not yet settled on that versus the original 'bare' representation.

- Fix syslog logging for syslog_timestamp=no and log_selector +millisec. Previously the millisecond value corrupted the output. Fix also for syslog_pid=no and log_selector +pid, for which the pid corrupted the output.

- Replace xorg-x11-devel by individual pkgconfig() buildrequires.

- update to 4.90.1

- Allow PKG_CONFIG_PATH to be set in Local/Makefile and use it correctly during configuration. Wildcards are allowed and expanded.

- Shorten the log line for daemon startup by collapsing adjacent sets of identical IP addresses on different listening ports. Will also affect 'exiwhat' output.

- Tighten up the checking in isip4 (et al): dotted-quad components larger than 255 are no longer allowed.

- Default openssl_options to include +no_ticket, to reduce load on peers. Disable the session-cache too, which might reduce our load. Since we currrectly use a new context for every connection, both as server and client, there is no benefit for these.

- Add $SOURCE_DATE_EPOCH support for reproducible builds, per spec at <https://reproducible-builds.org/specs/source-date-epoch />.

- Fix smtp transport use of limited max_rcpt under mua_wrapper. Previously the check for any unsuccessful recipients did not notice the limit, and erroneously found still-pending ones.

- Pipeline CHUNKING command and data together, on kernels that support MSG_MORE. Only in-clear (not on TLS connections).

- Avoid using a temporary file during transport using dkim. Unless a transport-filter is involved we can buffer the headers in memory for creating the signature, and read the spool data file once for the signature and again for transmission.

- Enable use of sendfile in Linux builds as default. It was disabled in 4.77 as the kernel support then wasn't solid, having issues in 64bit mode. Now, it's been long enough. Add support for FreeBSD also.

- Add commandline_checks_require_admin option.

- Do pipelining under TLS.

- For the 'sock' variant of the malware scanner interface, accept an empty cmdline element to get the documented default one. Previously it was inaccessible.

- Prevent repeated use of -p/-oMr

- DKIM: enforce the DNS pubkey record 'h' permitted-hashes optional field, if present.

- DKIM: when a message has multiple signatures matching an identity given in dkim_verify_signers, run the dkim acl once for each.

- Support IDNA2008.

- The path option on a pipe transport is now expanded before use

- Have the EHLO response advertise VRFY, if there is a vrfy ACL defined.

- Several bug fixes

- Fix for buffer overflow in base64decode() (boo#1079832 CVE-2018-6789)

Solution

Update the affected exim packages.

See Also

https://bugzilla.opensuse.org/show_bug.cgi?id=1079832

https://bugzilla.opensuse.org/show_bug.cgi?id=1171490

https://bugzilla.opensuse.org/show_bug.cgi?id=1171877

https://bugzilla.opensuse.org/show_bug.cgi?id=1173693

https://bugzilla.opensuse.org/show_bug.cgi?id=1185631

https://reproducible-builds.org/specs/source-date-epoch/

Plugin Details

Severity: Critical

ID: 149614

File Name: openSUSE-2021-677.nasl

Version: 1.3

Type: local

Agent: unix

Published: 5/18/2021

Updated: 11/22/2021

Dependencies: ssh_get_info.nasl

Risk Information

VPR

Risk Factor: Critical

Score: 9.4

CVSS v2

Risk Factor: Critical

Base Score: 10

Temporal Score: 8.7

Vector: AV:N/AC:L/Au:N/C:C/I:C/A:C

Temporal Vector: E:H/RL:OF/RC:C

CVSS v3

Risk Factor: Critical

Base Score: 9.8

Temporal Score: 9.4

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Temporal Vector: E:H/RL:O/RC:C

Vulnerability Information

CPE: p-cpe:/a:novell:opensuse:exim, p-cpe:/a:novell:opensuse:exim-debuginfo, p-cpe:/a:novell:opensuse:exim-debugsource, p-cpe:/a:novell:opensuse:eximon, p-cpe:/a:novell:opensuse:eximon-debuginfo, p-cpe:/a:novell:opensuse:eximstats-html, cpe:/o:novell:opensuse:15.2

Required KB Items: Host/local_checks_enabled, Host/SuSE/release, Host/SuSE/rpm-list, Host/cpu

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 5/7/2021

Vulnerability Publication Date: 6/19/2017

Exploitable With

CANVAS (CANVAS)

Metasploit (Exim 4.87 - 4.91 Local Privilege Escalation)

Reference Information

CVE: CVE-2017-1000369, CVE-2017-16943, CVE-2017-16944, CVE-2018-6789, CVE-2019-10149, CVE-2019-13917, CVE-2019-15846, CVE-2019-16928, CVE-2020-12783, CVE-2020-28007, CVE-2020-28008, CVE-2020-28009, CVE-2020-28010, CVE-2020-28011, CVE-2020-28012, CVE-2020-28013, CVE-2020-28014, CVE-2020-28015, CVE-2020-28016, CVE-2020-28017, CVE-2020-28018, CVE-2020-28019, CVE-2020-28020, CVE-2020-28021, CVE-2020-28022, CVE-2020-28023, CVE-2020-28024, CVE-2020-28025, CVE-2020-28026