CVE-2025-54885 json
Thinbus generates insufficient entropy: 252 bits vs minimum 256 bits
published 2025-08-06 15 mo ago modified 2026-06-17 4 mo ago also GHSA-8q6v-474h-whgg , EUVD-2025-23897
- cvss
- 6.9
- version 4.0, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.4%
- EPSS 0.4% chance of exploitation in 30 days, percentile 36%
- public exploits
- 0
- none known
Summary
Thinbus Javascript Secure Remote Password is a browser SRP6a implementation for zero-knowledge password authentication. In versions 2.0.0 and below, a protocol compliance bug causes the client to generate a fixed 252 bits of entropy instead of the intended bit length of the safe prime (defaulted to 2048 bits). The client public value is being generated from a private value that is 4 bits below the specification. This reduces the protocol's designed security margin it is now practically exploitable. The servers full sized 2048 bit random number is used to create the shared session key and password proof. This is fixed in version 2.0.1.
Patch / fix
- npm thinbus-srp 2.0.1
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- total
- Assessed
- 15 mo ago
Exploit prediction
0.42% chance of exploitation in the next 30 days, higher than 36% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 6.9 | CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:U |
| CNA | 4.0 | 6.9 | CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:U/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| npm | thinbus-srp | <2.0.1 |
2.0.1 |
Affected products
- simbo1905 thinbus-srp-npm
Classification
- Weakness
-
- CWE-331 Insufficient Entropy
References
-
github.com
/simbo1905/thinbus-srp-npm/pull/30/commits/4aeaea2366e090765a8204059c7bcf3616438d31
web
-
github.com
/simbo1905/thinbus-srp-npm/commit/aa7064c1db7294ce867e9bc92f26fa6c71a5a2cb
web
-
github.com
/simbo1905/thinbus-srp-npm/security/advisories/GHSA-8q6v-474h-whgg
web
-
github.com
/simbo1905/thinbus-srp-npm/issues/28
web
-
nvd.nist.gov
/vuln/detail/CVE-2025-54885
advisory
-
github.com
/simbo1905/thinbus-srp-npm
package
Sources
- CVE List CVE-2025-54885
- GitHub Advisory GHSA-8q6v-474h-whgg
- NVD CVE-2025-54885
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