CVE-2026-5082

Amon2::Plugin::Web::CSRFDefender versions from 7.00 through 7.03 for Perl generate an insecure session id. The generate_session_id function will attempt to read bytes from the /dev/urandom device, but if that is unavailable then it generates bytes using SHA-1 hash seeded with the built-in rand() function, the PID, and the high resolution epoch time. The PID will come from a small set of numbers, and the epoch time may be guessed, if it is not leaked from the HTTP Date header. The built-in rand function is unsuitable for cryptographic usage. Amon2::Plugin::Web::CSRFDefender versions before 7.00 were part of Amon2, which was vulnerable to insecure session ids due to CVE-2025-15604. Note that the author has deprecated this module.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://metacpan.org/release/TOKUHIROM/Amon2-Plugin-Web-CSRFDefender-7.03/source/lib/Amon2/Plugin/Web/CSRFDefender/Random.pm	Product
https://metacpan.org/release/TOKUHIROM/Amon2-Plugin-Web-CSRFDefender-7.04/changes	Release Notes
https://www.cve.org/CVERecord?id=CVE-2025-15604	Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:tokuhirom:amon2\:\:plugin\:\:web\:\:csrfdefender:*:*:*:*:*:perl:*:*

History

No history.

Information

Published : 2026-04-08 06:16

Updated : 2026-07-24 20:10

NVD link : CVE-2026-5082

Mitre link : CVE-2026-5082

CVE.ORG link : CVE-2026-5082

JSON object : View

Products Affected

tokuhirom

amon2\

CWE

CWE-338

Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG)

CWE-340

Generation of Predictable Numbers or Identifiers

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