Vulnerability Description
libexpat through 2.9.0 contains a signed integer overflow vulnerability in storeAtts() in lib/xmlparse.c that allows attackers to trigger out-of-bounds writes via oversized attribute counts. Attackers can supply a multi-gigabyte document with a start tag carrying over 2^30 attributes to overflow attIndex and nPrefixes, crashing applications or corrupting heap memory.
CVSS Score
MEDIUM
Related Weaknesses (CWE)
References
- https://github.com/libexpat/libexpat
- https://github.com/libexpat/libexpat/blob/a76b1174c1ea52abb639a4c69d52b630a8a106
- https://github.com/libexpat/libexpat/commit/1bac53c4fc460a03cd9860f39501c7979f67
- https://github.com/libexpat/libexpat/commit/621cb2c78b253ee023a86bc91d6ddb048481
- https://github.com/libexpat/libexpat/pull/1450
- https://www.vulncheck.com/advisories/libexpat-through-2.9.0-integer-overflow-in-
FAQ
What is CVE-2026-118370?
CVE-2026-118370 is a vulnerability with a CVSS score of 5.9 (MEDIUM). libexpat through 2.9.0 contains a signed integer overflow vulnerability in storeAtts() in lib/xmlparse.c that allows attackers to trigger out-of-bounds writes via oversized attribute counts. Attackers...
How severe is CVE-2026-118370?
CVE-2026-118370 has been rated MEDIUM with a CVSS base score of 5.9/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-118370?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.