Vulnerability 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 Score
CRITICAL
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Ktat | Http\ | <= 0.53, \ |
Related Weaknesses (CWE)
References
- https://metacpan.org/release/KTAT/http-session-0.53/source/lib/HTTP/Session/ID/MProduct
- https://metacpan.org/release/KTAT/http-session-0.53/source/lib/HTTP/Session/ID/SProduct
- https://security.metacpan.org/docs/guides/random-data-for-security.htmlThird Party Advisory
- http://www.openwall.com/lists/oss-security/2026/03/28/5Mailing ListThird Party Advisory
FAQ
What is CVE-2026-3256?
CVE-2026-3256 is a vulnerability with a CVSS score of 9.8 (CRITICAL). 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 see...
How severe is CVE-2026-3256?
CVE-2026-3256 has been rated CRITICAL with a CVSS base score of 9.8/10. This is considered a critical vulnerability requiring immediate attention.
Is there a patch for CVE-2026-3256?
Check the references section above for vendor advisories and patch information. Affected products include: Ktat Http\.