AEGLIX vulnerability intelligence
CVE-2026-65632
MEDIUM · CVSS 5.1 · Deferred
Published: 2026-10-26 · Updated: 2026-10-27 · Source: NVD
Stored catalog record
Source record retrieved 2026-10-28T10:27:24.869913+00:00. Scheduled imports handle updates; this page does not assert that the provider was queried just now.
Vulnerability overview
The jose library accepts ECDSA (ES256, ES256K, ES384, and ES512) JWS signatures of a non-canonical length. When verifying an ECDSA signature, jose_jwk_kty_ec:verify/4 in src/jwk/jose_jwk_kty_ec.erl splits the raw signature in half by its actual byte length (split_binary(Signature, byte_size(Signature) div 2)) instead of enforcing the fixed length required by RFC 7518 §3.4, and then decodes each half with crypto:bytes_to_integer/1, which ignores leading zero bytes. As a result, an attacker who holds one valid token can prepend leading zero bytes to each of the R and S halves to produce longer signatures that still split evenly and decode to the same (r, s) pair, so many distinct signature byte strings all verify against the same key (signature malleability). This does not allow forging new payloads or impersonating a signer, because the underlying (r, s) values are unchanged. It does defeat any security control that assumes a valid token or its signature is unique, such as token-revocation-by-hash, replay or idempotency caches, and deduplication logic. This issue affects jose: from 1.0.0 before 1.11.13.
Patch review priority
Assess exposure and vendor guidance
- No higher-priority signal is available in the current stored evidence.
FIRST EPSS: 0.09% · percentile 0.5 · score date 2026-10-27.
EPSS estimates probability of exploitation in the next 30 days. It does not measure your exposure or prove exploitation. The elevated threshold is 10%; CISA KEV takes precedence. About FIRST EPSS ↗
Severity and scoring
- CVSS score
- 5.1 · MEDIUM
- CVSS version
- 4.0
- CVSS vector
- CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/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
- Weaknesses
- CWE-347
CVSS measures technical severity; it does not establish whether this vulnerability is being exploited in your environment.
Known exploitation and remediation
Not listed in the CISA catalog retrieved for this record. This does not establish that exploitation has not occurred.
Verify affected versions and patch availability in the vendor advisory before making changes.
Affected products and versions
NVD has not supplied affected-version configurations for this record. Check the vendor references below.
Advisories and references
- https://cna.erlef.org/cves/CVE-2026-65632.html
- https://github.com/potatosalad/erlang-jose/commit/72ce1866622b9329347dc52a94173ac0317bc9cf
- https://github.com/potatosalad/erlang-jose/commit/a7746ecd4950f85a393136e449a91dac62b5c429
- https://github.com/potatosalad/erlang-jose/security/advisories/GHSA-44hw-rpw9-mwg4
- https://osv.dev/vulnerability/EEF-CVE-2026-65632