CVE-2022-37434 — zlib through 1

zlib through 1.2.12 has a heap-based buffer over-read or buffer overflow in inflate in inflate.c via a large gzip header extra field. NOTE: only applications that call inflateGetHeader are affected. Some common applications bundle the affected zlib source code but may be unable t

01What is this vulnerability?

zlib through 1.2.12 has a heap-based buffer over-read or buffer overflow in inflate in inflate.c via a large gzip header extra field. NOTE: only applications that call inflateGetHeader are affected. Some common applications bundle the affected zlib source code but may be unable to call inflateGetHeader (e.g., see the nodejs/node reference).

02Affected products

No structured affected-product list available — see references below for vendor advisories.

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: 2022-08-05T07:15:07.240
• Last modified: 2026-10-14T18:17:03.630

09References

• seclists.org — http://seclists.org/fulldisclosure/2022/Oct/37
• seclists.org — http://seclists.org/fulldisclosure/2022/Oct/38
• seclists.org — http://seclists.org/fulldisclosure/2022/Oct/41
• seclists.org — http://seclists.org/fulldisclosure/2022/Oct/42
• www.openwall.com — http://www.openwall.com/lists/oss-security/2022/08/05/2
• www.openwall.com — http://www.openwall.com/lists/oss-security/2022/08/09/1
• github.com — https://github.com/curl/curl/issues/9271
• github.com — https://github.com/ivd38/zlib_overflow
• github.com — https://github.com/madler/zlib/blob/21767c654d31d2dccdde4330529775c6c5fd5389/zli…
• github.com — https://github.com/madler/zlib/commit/1eb7682f845ac9e9bf9ae35bbfb3bad5dacbd91d