Vulnerability in Bluefeet Starch
CVE-2025-40925
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.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 9.1 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N.
EPSS exploit prediction
EPSS: 0.004 (27.5th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 27th percentile — 27.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: 0.000
Affected products
- Bluefeet Starch — versions 0.01
Weakness classification (CWE)
Public proof-of-concept exploits
References
Frequently asked questions
- What is CVE-2025-40925?
- CVE-2025-40925 is a critical-severity vulnerability in Bluefeet Starch, classified under Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG). CVSS score: 9.1/10. Published 2025-09-20.
- How severe is CVE-2025-40925?
- Critical severity. CVSS v3 base score is 9.1 out of 10.
- Is CVE-2025-40925 known to be exploited?
- 2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.