CVE-2026-3256

HTTP::Session versions before 0.54 for Perl defaults to using insecurely generated session ids. HTTP::Session defaults to using HTTP::Session::ID::SHA1 to generate session ids using a SHA-1 hash seeded with the built-in rand function, the high resolution epoch time, and the PID. 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. The distribution includes HTTP::session::ID::MD5 which contains a similar flaw, but uses the MD5 hash instead.

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://metacpan.org/release/KTAT/http-session-0.53/source/lib/HTTP/Session/ID/MD5.pm	Product
https://metacpan.org/release/KTAT/http-session-0.53/source/lib/HTTP/Session/ID/SHA1.pm	Product
https://metacpan.org/release/TOKUHIROM/http-session-0.54/changes
https://security.metacpan.org/docs/guides/random-data-for-security.html	Third Party Advisory
http://www.openwall.com/lists/oss-security/2026/03/28/5	Mailing List Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:ktat:http\:\:session:*:*:*:*:*:perl:*:*

History

No history.

Information

Published : 2026-03-28 19:16

Updated : 2026-06-29 07:16

NVD link : CVE-2026-3256

Mitre link : CVE-2026-3256

CVE.ORG link : CVE-2026-3256

JSON object : View

Products Affected

ktat

http\

CWE

CWE-338

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

CWE-340

Generation of Predictable Numbers or Identifiers

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