CVE-2026-8503: GUIMARD Apache::Session::Generate::SHA256 · Generation of Predictable Numbers or Identifiers
Affects GUIMARD Apache::Session::Generate::SHA256Source CVE Database V5
Not known to be exploited · CVSS 6.5 Medium : upgrade to 1.3.19 when convenient.
Data as of 30 Oct 2026, 11:52 UTC
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 15% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 1.3.19
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:NExploitation evidence
Disclosed: evidence found.
CVE published 15 May 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 30 Oct 2026.
What to do
Upgrade Apache::Session::Generate::SHA256 and Apache-Session-Browsable to 1.3.19.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| GUIMARDApache::Session::Generate::SHA256 | Affected
| Fixed in
|
GitHubApache-Session-Browsablepkg:github/Apache-Session-BrowsableOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Since version 1.3.19 attempts to use a more secure method with a fallback to the insecure method only if Crypt::URandom::urandom fails, ensuring that Crypt::URandom is properly installed and functional may mitigate fallback risks. Consider avoiding use of affected versions or implementing additional session security controls until an official fix is released.
Description
CVE-2026-8503 is a medium severity vulnerability in Apache::Session::Generate::SHA256 versions before 1.3.19 for Perl. The module generates session IDs using predictable, low-entropy sources such as the built-in rand() function, epoch time, and process ID, which are hashed with SHA-256. This predictability can allow attackers to guess session IDs and potentially gain unauthorized access. Version 1.3.19 includes a fallback to an insecure method only if Crypt::URandom::urandom fails, which is unlikely since Crypt::URandom is a required dependency.
References
- metacpan.org/release/GUIMARD/Apache-Session-Browseable-1.3.19/changes (opens in a new tab)
- metacpan.org/release/GUIMARD/Apache-Session-Browseable-1.3.19/diff/GUIMARD/Apache-Session-Browseable-1.3.18 (opens in a new tab)
- github.com/LemonLDAPNG/Apache-Session-Browseable/commit/cc915cbbd266776eec3dd8bf4748b15fa827dbd0.patch (opens in a new tab)
- cve.org/CVERecord?id=CVE-2025-40931 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2025-40932 (opens in a new tab)