CVE-2026-89086 jose OCaml - Authentication Bypass

jose package for OCaml < 0.11.0 contains a broken authentication caused by incomplete RSA signature validation that only checks PKCS #1 decoding without verifying the public key, letting attackers bypass signature verification, exploit requires crafted signature input.

CVSS base score 9.1 /10
Critical
CISA KEV
Not listed
Public exploit
None known
Authentication
Not required
EPSS
0.28% chance of exploitation in 30 days
View the NVD record ↗

Details

Type
Authentication Bypass
Impact
Broken Authentication
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Published
10 September 2026
Updated
15 October 2026
Weakness
CWE-347

Vendor fix

Update to version 0.11.0 or later.

Patching closes this CVE. It does not tell you which of your systems run the affected version, or what else is exposed alongside them.

References

← All CVEs