CVE-2023-52426 — libexpat through 2

libexpat through 2.5.0 allows recursive XML Entity Expansion if XML_DTD is undefined at compile time.

01What is this vulnerability?

libexpat through 2.5.0 allows recursive XML Entity Expansion if XML_DTD is undefined at compile time.

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: 2024-02-04T20:15:46.120
• Last modified: 2026-10-15T01:17:13.283

09References

• cwe.mitre.org — https://cwe.mitre.org/data/definitions/776.html
• github.com — https://github.com/libexpat/libexpat/commit/0f075ec8ecb5e43f8fdca5182f8cca4703da…
• github.com — https://github.com/libexpat/libexpat/pull/777
• lists.fedoraproject.org — https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedorapro…
• lists.fedoraproject.org — https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedorapro…
• security.netapp.com — https://security.netapp.com/advisory/ntap-20240307-0005/
• cwe.mitre.org — https://cwe.mitre.org/data/definitions/776.html
• github.com — https://github.com/libexpat/libexpat/commit/0f075ec8ecb5e43f8fdca5182f8cca4703da…
• github.com — https://github.com/libexpat/libexpat/pull/777
• lists.fedoraproject.org — https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedorapro…