Vulnerability · Published Sep 20, 2025 · Assigned by CPANSec

CVE-2025-40925Starch versions 0.14 and earlier generate session ids insecurely

Critical 9.1

In plain English

A critical-severity security flaw in Starch from BLUEFEET. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 30% of all known vulnerabilities).

Severity (CVSS 3.1)9.1Critical
Exploit odds (30 days)0.4%top 70.1% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official description

Starch versions 0.14 and earlier generate session ids insecurely. The default session id generator returns a SHA-1 hash seeded with a counter, the epoch time, the built-in rand function, the PID, and internal Perl reference addresses. 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. Predicable session ids could allow an attacker to gain access to systems.

Affected products (as reported)

VendorProductVersions
BLUEFEET Starch 0.01 – through 0.14

Weakness: CWE-340, CWE-338 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

References