CVE-2026-32600: xml-security is Missing AES-GCM Authentication Tag Validation on Encrypted Nodes Allows for Unauthorized Decryption
Vulnerability summary
CVE-2026-32600 is a high (CVSS 8.2) vulnerability in simplesamlphp xml-security. EPSS estimates a 0.17% chance of exploitation in the next 30 days, higher than 6.3% of scored vulnerabilities. 1 public exploit is recorded.
Timeline
- 13-03-2026PublishedVulnerability first disclosed.
- 16-03-2026Last modifiedVulnerability information updated.
Description
xml-security is a library that implements XML signatures and encryption. Prior to versions 2.3.1 and 1.13.9, XML nodes encrypted with either aes-128-gcm, aes-192-gcm, or aes-256-gcm lack validation of the authentication tag length. An attacker can use this to brute-force an authentication tag, recover the GHASH key, and decrypt the encrypted nodes. It also allows to forge arbitrary ciphertexts without knowing the encryption key. This vulnerability is fixed in 2.3.1 and 1.13.9.
CVSS metrics
2 scores · 2 sources · 1 version- NVDNIST8.2HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N
EPSS trend
Probability
0.17%
Chance of exploitation in the next 30 days
Percentile
6%
Versus all other CVEs
30-day change
Increase +0.03 pp
From 0.15% on 22-09-2026
Known exploited
Compare KEV catalogs
CISA KEVNot in the CISA KEV catalog.
ENISA CNWNot in the ENISA CNW catalog.
CIRCLNot in the CIRCL catalog.
Public exploits
1 foundXml Security
Maturity: poc
Weaknesses
CWE · root causeAffected systems
Simplesamlphp1 product
- xml-security< 1.13.9 | ≥ 2.0.0, < 2.3.1
1 vendor · 1 product
References
3 links- github.com/simplesamlphp/xml-security/security/advisories/GHSA-r353-4845-pr5pX Refsource CONFIRMExploitVendor Advisory