CVE-2026-5500
Improper Validation of AES-GCM Authentication Tag Length in PKCS#7 Envelope Allows Authentication Bypass
Summary
Improper Validation of AES-GCM Authentication Tag Length in PKCS#7 Envelope Allows Authentication Bypass
Original description
The description as published by the source.
wolfSSL's wc_PKCS7_DecodeAuthEnvelopedData() does not properly sanitize the AES-GCM authentication tag length received and has no lower bounds check. A man-in-the-middle can therefore truncate the mac field from 16 bytes to 1 byte, reducing the tag check from 2⁻¹²⁸ to 2⁻⁸.
Fix status by distribution
Fixed packages published by each distribution for this CVE
- Debian DEBIAN-CVE-2026-5500 wolfssl
- Ubuntu UBUNTU-CVE-2026-5500 wolfssl
References
- advisory github.com
- advisory nvd.nist.gov
- patch github.com