Machine-written summary
Summary written by Claude Haiku from the source advisory. Not reviewed by a person.
The simplesamlphp/xml-security package versions below 1.13.9, and from 2.0.0 up to but not including 2.3.1, do not check the length of the authentication tag when decrypting XML nodes encrypted with AES-GCM. An attacker who can submit crafted encrypted XML to an affected service can brute-force the tag, recover the GHASH key, and then decrypt or forge encrypted nodes. Upgrade to version 1.13.9 or 2.3.1. If static symmetric keys are used, rotate them, since the GHASH key may have been exposed.
Not analysed yet
We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.
Severity and exploitation
| Score | Rating | CVSS | Vector | Source |
|---|---|---|---|---|
| 8.2 | High | 3.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N | CNA (GitHub_M) |
- CISA KEV Not listed.
- EPSS 0.0015, the 4th percentile, on 5 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.
Timeline
- 31 Oct 2026, 14:26 UTC First seen by agentprime
- 31 Oct 2026, 14:26 UTC Confirmed by OSV
Sources
- GitHub Advisory Database: GHSA-r353-4845-pr5p
- OSV: GHSA-r353-4845-pr5p
- github.com/simplesamlphp/xml-security/security/advisories/GHSA-r353-4845-pr5p
- nvd.nist.gov/vuln/detail/CVE-2026-32600
- github.com/simplesamlphp/xml-security/commit/cad6d57cf0a5a0b7e0cc4e4a5b18752e56eb1520
- github.com/simplesamlphp/xml-security/commit/fdc12449e959c610943f9fd428e95e3832d74c25
- github.com/simplesamlphp/xml-security