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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-56016 Detail

Description

CGI::Session::ID::md5 versions before 4.49 for Perl generate predictable session ids from low-entropy sources. The generate_id method builds the session id from a MD5 digest of the process id, the epoch time, and the built-in rand() function. All three are predictable, low-entropy sources: the PID is drawn from a small range, the epoch time can be guessed or read from the HTTP Date header, and Perl's rand() is unsuitable for security purposes because it is predictable and reversible. An attacker who predicts a session id can impersonate the corresponding session and bypass authentication.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
http://www.openwall.com/lists/oss-security/2026/07/01/6 CVE
https://metacpan.org/release/MARKSTOS/CGI-Session-4.49/changes CPANSec
https://metacpan.org/release/MARKSTOS/CGI-Session-4.49/source/lib/CGI/Session/ID/md5.pm CPANSec

Weakness Enumeration

CWE-ID CWE Name Source
CWE-338 Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG) CPANSec  
CWE-340 Generation of Predictable Numbers or Identifiers CPANSec  

Change History

3 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-56016
NVD Published Date:
07/01/2026
NVD Last Modified:
07/01/2026
Source:
CPANSec