CVE-2022-37452 — Exim before 4

Exim before 4.95 has a heap-based buffer overflow for the alias list in host_name_lookup in host.c when sender_host_name is set.

01What is this vulnerability?

Exim before 4.95 has a heap-based buffer overflow for the alias list in host_name_lookup in host.c when sender_host_name is set.

02Affected products

Vendor	Product	Versions
n	a / n/a	n/a

03Active exploitation status

Not currently listed on the CISA Known Exploited Vulnerabilities (KEV) catalog. EPSS is the best forward-looking signal — see the EPSS row above.

04Recommended remediation

• Patch to a fixed version listed in the vendor advisory (see references below).
• Mitigate with WAF rules, network egress filters, or feature flags where the patch is not yet available.
• Hunt historical logs for exploitation indicators — see Detection signatures below.

05Technical details

For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.

06Detection signatures

Ask SARA in chat to draft a starting detection for this CVE in your stack of choice.

07Related CVEs

No directly-cited follow-up CVEs in the KB record for this advisory. The references list in section 09 carries the vendor cross-references.

08Timeline

• Published: 2022-08-07T17:06:55.000Z
• Last modified: 2024-08-03T10:29:21.079Z

09References

• github.com — https://github.com/Exim/exim/wiki/EximSecurity
• www.exim.org — https://www.exim.org/static/doc/security/
• github.com — https://github.com/ivd38/exim_overflow
• www.openwall.com — https://www.openwall.com/lists/oss-security/2022/08/06/8
• github.com — https://github.com/Exim/exim/compare/exim-4.94...exim-4.95
• github.com — https://github.com/Exim/exim/commit/d4bc023436e4cce7c23c5f8bb5199e178b4cc743
• lists.debian.org — https://lists.debian.org/debian-lts-announce/2022/08/msg00014.html