CVE-2026-3255
mediumpriority · track · 26EPSS 0.005 · 40 %ileEUUSEPSS · scored 2026-10-27
HTTP::Session2 versions before 1.12 for Perl for Perl may generate weak session ids using the rand() function. The HTTP::Session2 session id generator returns a SHA-1 hash seeded with the built-in rand function, the 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. HTTP::Session2 after version 1.02 will attempt to use the /dev/urandom device to generate a session id, but if the device is unavailable (for example, under Windows), then it will revert to the insecure method described above.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (2)
Products and version ranges known to be affected.
also known as (3)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (15)
External citations — patches, advisories, analysis.
- http://www.openwall.com/lists/oss-security/2026/02/27/12cnnvd
- https://access.redhat.com/security/cve/cve-2026-3255cnnvd
- https://github.com/tokuhirom/HTTP-Session2/commit/9cfde4d7e0965172aef5dcfa3b03bb48df93e636.patchcnnvd
- https://metacpan.org/release/TOKUHIROM/HTTP-Session2-1.01/source/lib/HTTP/Session2/ServerStore.pm#L68cnnvd
- https://metacpan.org/release/TOKUHIROM/HTTP-Session2-1.11/source/lib/HTTP/Session2/Random.pm#L35cnnvd
- https://metacpan.org/release/TOKUHIROM/HTTP-Session2-1.12/changescnnvd
- https://github.com/tokuhirom/HTTP-Session2/commit/9cfde4d7e0965172aef5dcfa3b03bb48df93e636.patchenisa_euvd
- https://metacpan.org/release/TOKUHIROM/HTTP-Session2-1.01/source/lib/HTTP/Session2/ServerStore.pm#L68enisa_euvd
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