CVE-2026-5081
Description
A flaw was found in Apache::Session::Generate::ModUniqueId, a Perl module designed to generate session identifiers. This module uses the Apache mod_unique_id plugin's UNIQUE_ID environment variable directly as a session ID. The UNIQUE_ID is constructed from easily guessable information, such as the server's IP address, process ID, and timestamp, without sufficient randomness or obfuscation. This predictability allows a remote attacker to potentially guess valid session IDs, which could lead to session hijacking and unauthorized access to user accounts or sensitive information.
Mitigation
To mitigate this issue, applications utilizing Apache::Session should be reconfigured to use a cryptographically secure session ID generation mechanism instead of Apache::Session::Generate::ModUniqueId. For example, consider using Apache::Session::Generate::MD5, Apache::Session::Generate::SHA256, or Apache::Session::Generate::Random, which provide stronger randomness for session identifiers. Consult your application's documentation for specific configuration instructions.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
The following CVSS metrics and score provided are preliminary and subject to review.
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 8.2 | N/A | 8.2 |
| Attack Vector | Network | N/A | Network |
| Attack Complexity | Low | N/A | Low |
| Privileges Required | None | N/A | None |
| User Interaction | None | N/A | None |
| Scope | Unchanged | N/A | Unchanged |
| Confidentiality | High | N/A | High |
| Integrity Impact | Low | N/A | Low |
| Availability Impact | None | N/A | None |
Vector
Red Hat: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N
cve.org: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N
Understanding the Weakness (CWE)
Other
Technical Impact: Varies by Context
This weakness could be exploited by an attacker in a number ways depending on the context. If a predictable number is used to generate IDs or keys that are used within protection mechanisms, then an attacker could gain unauthorized access to the system. If predictable filenames are used for storing sensitive information, then an attacker might gain access to the system and may be able to gain access to the information in the file.
Frequently Asked Questions
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