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CVE-2026-3256

Published: Mar 28, 2026Updated: Apr 1, 2026 Sources: CVE List NVDCWE-338
NVD MITRE
9.8CVSSCRITICAL
EPSS Score
0.5%
Top 59.5%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Workaround Only

Description

HTTP::Session versions through 0.53 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 Vector Breakdown

AV:NAC:LPR:NUI:NS:UC:HI:HA:H
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:HConfidentiality
High
I:HIntegrity
High
A:HAvailability
High
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Weaknesses

CWE-338CWE-340

Affected Products

HTTP::SessionKTAT
Library
OSS Libraries / generic-library
http\ktat
Library
OSS Libraries / generic-library
ktatpackage-ecosystemOSS Libraries

Exploitability

Workaround Available

References

https://metacpan.org/release/KTAT/http-session-0.53/source/lib/HTTP/Session/ID/SHA1.pm
metacpan.org
https://metacpan.org/release/KTAT/http-session-0.53/source/lib/HTTP/Session/ID/MD5.pm
metacpan.org
https://security.metacpan.org/docs/guides/random-data-for-security.html
security.metacpan.org
and 1 more references View all →

Timeline

Published
Mar 28, 2026
Last Updated
Apr 1, 2026

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