CVE-2026-5081
What it is
Apache::Session::Generate::ModUniqueId versions from 1.54 through 1.94 for Perl session ids are insecure. Apache::Session::Generate::ModUniqueId (added in version 1.54) uses the value of the UNIQUE_ID environment variable for the session id. The UNIQUE_ID variable is set by the Apache mod_unique_id plugin, which generates unique ids for the request. The id is based on the IPv4 address, the process id, the epoch time, a 16-bit counter and a thread index, with no obfuscation. The server IP is often available to the public, and if not available, can be guessed from previous session ids being issued. The process ids may also be guessed from previous session ids. The timestamp is easily guessed (and leaked in the HTTP Date response header). The purpose of mod_unique_id is to assign a unique id to requests so that events can be correlated in different logs. The id is not designed, nor is it suitable for security purposes.
At a glance
- Exploitability
- Can be exploited over the network without logging in. High risk of data exposure, data tampering.
- Exploit odds
- 0.3% chance of exploitation in the next 30 days (EPSS).
- Fix
- No patch or advisory is linked yet. Look at mitigations or restrict exposure.
Timeline
- ReservedThe CVE id was reserved by its CNA
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.3% in the next 30 days (EPSS).
- Severity: 9.1 CRITICAL (CVSS).
- Fix: none linked yet, which raises it.
Details
- Published
- Last modified
- Exploit probability
- 0.3% · EPSS, next 30 days
- Weakness
- CWE-340
- Record status
- Modified
Affected
- Chorny apache\ ≤ 1.94
Attack profile CVSS 3.1 · 9.1
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- None
Raw vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2026-5081.md and follow it. Check whether this project is affected by CVE-2026-5081. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
References
- https://httpd.apache.org/docs/current/mod/mod_unique_id.html
- https://metacpan.org/pod/Apache::Session::Generate::Random
- http://www.openwall.com/lists/oss-security/2026/05/06/6
- https://access.redhat.com/security/cve/CVE-2026-5081
- https://bugzilla.redhat.com/show_bug.cgi?id=2467174
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-5081.json