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TI-2026-60369 Aliases CVE-2026-89086GHSA-9r5j-37q2-cffw

Improper signature verification in OCaml jose

Priority HIGH 80CWE-347Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Security bypass
Confidentiality · integrity · availability
High · High · None
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-347.

Summary

In the jose package before 0.11.0 for OCaml, library calls to validate an RSA signature only confirm that PKCS #1 decoding succeeds, and proceed to declare the signature valid without the required steps that involve the public key.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00276 20th percentileScored 2026-11-07
Fix Fixed jose (OCaml): 0.11.0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
Yes
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
OCamljosebefore 0.11.00.11.0Patch availableCNA
  • jose VendorOCaml Affected before 0.11.0 Fixed in 0.11.0 Patch available CNA

Remediation

  • Fix · CNA jose (OCaml) Fixed in 0.11.0

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-89086
  2. 2026-10-03 Alias added: GHSA-9r5j-37q2-cffw

References

Other 2

  • TI-2026-59889 An issue was discovered in the utcp package before 0.0.6 for OCaml. CVSS 3.1HIGH 7.5
  • TI-2026-29719 In OCaml opam before 2.5.1, a .install field containing a destination filepath can use ../ to reach a parent directory. CVSS 3.1HIGH 7.8
  • TI-2026-59888 Improper certificate validation in OCaml mirage-crypto-ec CVSS 3.1MEDIUM 6.2
  • TI-2026-59887 Improper signature verification in OCaml mirage-crypto CVSS 3.1MEDIUM 6.2
  • TI-2018-07003 The caml_ba_deserialize function in byterun/bigarray.c in the standard library in OCaml… CVSS 3.0CRITICAL 9.8
  • TI-2017-07154 Insufficient sanitisation in the OCaml compiler versions 4.04.0 and 4.04.1 allows… CVSS 3.0CRITICAL 9.8
See all 16 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences