Categories
CVE-2026-59163 critical CVSS 9.1

Vulnerability in mnemosyne-memory (CVE-2026-59163)

Summary

Vulnerability in mnemosyne-memory (CVE-2026-59163). Confidential information can be exposed externally. Mitigation: upgrade to 3.10.1 or later.

Original description

The description as published by the source.

Summary

The Mnemosyne sync server's authentication check decoded JWT bearer tokens but never verified their HMAC-SHA256 signatures. Any well-formed token was accepted, allowing an unauthenticated attacker to impersonate any user and read or modify their sync data.

Severity: Critical

CVSS 3.1: AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N = 9.1

Assumes the sync server endpoint is network-reachable. If your deployment is localhost-only, the score drops substantially and severity becomes High or Medium depending on local exposure. Confirm your threat model.

Affected versions

All mnemosyne versions exposing the sync server endpoint, up to and including v3.10.0.

Patched versions

v3.10.1 (commit a0b6b871 on branch security/jwt-signature-verification)


Description

The sync server uses JWT bearer tokens to authenticate clients. 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:

  • Constant-time signature comparison via hmac.compare_digest
  • Strict alg: HS256 check, rejecting none and other algorithms
  • UTC-aware exp validati…

Source: NIST National Vulnerability Database NVD GitHub Advisory

Auto-generated summary

Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.

A vulnerability tracked as CVE-2026-59163 has been found in mnemosyne-memory.
Confidential information can be exposed externally. CVSS score: 9.1/10.
What to do: upgrade mnemosyne-memory to 3.10.1 or later.
If unsure, ask your IT team or search "mnemosyne-memory CVE-2026-59163" on the vendor's site.

CVE-2026-59163 (mnemosyne-memory) — CWE-347 / CVSS v3 9.1
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Patched: 3.10.1 — apply immediately
Workaround: None.
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.

❓ What is the problem

A vulnerability (CWE-347) exists in mnemosyne-memory.

📍 Affected scope

Check the vendor advisory for the affected versions of mnemosyne-memory.

🔥 Severity

Severity: Critical (CVSS 9.1/10). Confidential information can be exposed externally.

🔧 How to fix

Update to 3.10.1.

🛡️ Workaround

Workaround: None.

🔍 Detection

Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'mnemosyne-memory' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.

Response actions

Concrete steps and command examples for SOC/SRE teams to execute in order

  1. 1
    Identify exposure identify
    grep -r 'mnemosyne-memory' . | grep -v node_modules

    リポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で mnemosyne-memory を grep し、稼働しているサービス・バージョンを把握する。

  2. 2
    Apply temporary workaround mitigate
    None.

    パッチが適用されるまでの応急処置として、None. を実施。回避策の副作用 (機能低下) を確認した上で。

  3. 3
    Apply patch patch
    Upgrade mnemosyne-memory to 3.10.1

    ステージング環境で 3.10.1 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。

  4. 4
    Post-deployment verification verify
    Confirm patched version is live in production

    パッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。

Affected packages

pip mnemosyne-memory
[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.10.1"}]}]

References

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