CVE-2025-45765: ruby-jwt v3.0.0.beta1 was discovered to contain weak encryption
Affects ruby-jwtSource GCVE Database
Not known to be exploited · CVSS 9.1 Critical.
Data as of 12 Nov 2026, 19:47 UTC
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 7 Aug 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 12 Nov 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.10ruby-jwtpkg:deb/ubuntu/ruby-jwt?arch=source&distro=stonkingOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSruby-jwtpkg:deb/ubuntu/ruby-jwt?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 25.10ruby-jwtpkg:deb/ubuntu/ruby-jwt?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSruby-jwtpkg:deb/ubuntu/ruby-jwt?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Ubuntu Pro 22.04 LTSruby-jwtpkg:deb/ubuntu/ruby-jwt?arch=source&distro=esm-apps/jammyOther threats | Affected
| Fixed in– |
Ubuntu Pro 20.04 LTSruby-jwtpkg:deb/ubuntu/ruby-jwt?arch=source&distro=esm-apps/focalOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Users should ensure they use recent OpenSSL versions that enforce appropriate key sizes, as the library itself does not enforce this. Monitoring for vendor advisories or updates to ruby-jwt is recommended to obtain any future patches addressing this issue.
Description
ruby-jwt version 3.0.0.beta1 contains weak encryption due to lack of enforced key size restrictions. The supplier notes that key size enforcement is not handled by the library itself but relies on underlying OpenSSL versions. This vulnerability has a critical CVSS score of 9.1, indicating high confidentiality impact and high availability impact without integrity impact. Multiple specific versions of ruby-jwt are affected.