Use After Free Affecting exim package, versions <0:4.89-4.17.amzn1
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Test your applications- Snyk IDSNYK-AMZN201803-EXIM-1709470
- published27 Sept 2021
- disclosed25 Nov 2017
Introduced: 25 Nov 2017
CVE-2017-16943 (opens in a new tab)How to fix?
Upgrade Amazon-Linux:2018.03 exim to version 0:4.89-4.17.amzn1 or higher.
This issue was patched in ALAS-2017-932.
NVD Description
Note: Versions mentioned in the description apply only to the upstream exim package and not the exim package as distributed by Amazon-Linux.
See How to fix? for Amazon-Linux:2018.03 relevant fixed versions and status.
The receive_msg function in receive.c in the SMTP daemon in Exim 4.88 and 4.89 allows remote attackers to execute arbitrary code or cause a denial of service (use-after-free) via vectors involving BDAT commands.
References
- http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2017-16943
- https://www.debian.org/security/2017/dsa-4053
- http://openwall.com/lists/oss-security/2017/11/25/1
- http://openwall.com/lists/oss-security/2017/11/25/2
- http://openwall.com/lists/oss-security/2017/11/25/3
- https://bugs.exim.org/show_bug.cgi?id=2199
- https://git.exim.org/exim.git/commit/4090d62a4b25782129cc1643596dc2f6e8f63bde
- https://git.exim.org/exim.git/commitdiff/4e6ae6235c68de243b1c2419027472d7659aa2b4
- https://github.com/LetUsFsck/PoC-Exploit-Mirror/tree/master/CVE-2017-16944
- https://lists.exim.org/lurker/message/20171125.034842.d1d75cac.en.html
- http://www.openwall.com/lists/oss-security/2021/05/04/7
- http://www.securitytracker.com/id/1039872