CVE-2026-8503 PUBLISHED

Apache::Session::Generate::SHA256 versions before 1.3.19 for Perl create insecure session ids.

Apache::Session::Generate::SHA256 generated session ids insecurely. The default session id generator returns a SHA-256 hash of the built-in rand() function, the epoch time, and the PID, that is hashed again. These are predictable, low-entropy sources. Predicable session ids could allow an attacker to gain access to systems.

Note that version 1.3.19 has a fallback without warning to use insecure session generation method if the call to Crypt::URandom::urandom fails. However, this is unlikely as Crypt::URandom is a hardcoded requirement of the module.

This issue is similar to CVE-2025-40931 for Apache::Session::Generate::MD5.

Upgrade to version 1.3.19 or later.

• https://metacpan.org/release/GUIMARD/Apache-Session-Browseable-1.3.19/changes
• https://metacpan.org/release/GUIMARD/Apache-Session-Browseable-1.3.19/diff/GUIMARD/Apache-Session-Browseable-1.3.18#lib/Apache/Session/Generate/SHA256.pm
• https://github.com/LemonLDAPNG/Apache-Session-Browseable/commit/cc915cbbd266776eec3dd8bf4748b15fa827dbd0.patch
• https://www.cve.org/CVERecord?id=CVE-2025-40931
• https://www.cve.org/CVERecord?id=CVE-2025-40932

• CWE-340 Generation of Predictable Numbers or Identifiers CWE
• CWE-338 Use of Cryptographically Weak Pseudo-Random Number Generator CWE

• CAPEC-115 Authentication Bypass
• CAPEC-102 Session Sidejacking