CVE-2026-59163

LOWCVSS 9.1 · CRITICAL

Signal is active with 1 mentions in latest observed window

Immediate actions

  • Track advisory updates for patch or workaround availability

Recommended action window: Monitor and triage in normal cycle

NVD description

Mnemosyne is a memory layer for artificial intelligence agents. Prior to v3.10.1, the auth check in mnemosyne/core/sync_server.py parsed the JWT's header and payload using base64 decoding, then passed the token to a jwt library call with options that effectively disabled signature verification. The server accepted any well-formed token regardless of the signature, including tokens with alg: none and tokens signed with the wrong key. The fix in v3.10.1 replaces the broken decode with a from-scratch HS256 verifier using only the Python standard library. For users who cannot upgrade immediately, restrict network access to the sync server endpoint to trusted clients only. Firewall, reverse proxy with mTLS, or localhost bind with SSH tunnel are all viable. The vulnerability is not exploitable against an unreachable endpoint.

0.0/ 10 priority

Sources & remediation

Weakness type (CWE)
CWE-347

Priority

LOW

Exploitation

NONE

PoC

NONE

Patch

NONE

Momentum

NONE

Threat summary

  • 1 mentions across 1 observed day

What's happening

  • 1 total mentions across 1 day

Deep dive

Activity timeline1 mentions / 1d
00111Mentions · 2026-09-21: 109-21
Referenced assets1 URL
By indicator
Full discourse1 post
  • Orizon Signals@OrizonSignals

    CVE-2026-59163: Mnemosyne sync server decoded JWT tokens but skipped HMAC-SHA256 signature checks, letting any well-formed token impersonate a user. First step: confirm your deployment actually verifies signatures, not just token structure. https://github.com/advisories/GHSA-xcw4-53cc-hv32 https://t.co/Wv7ONIdjVK

    0000022
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