CVE-2026-39413 (GCVE-0-2026-39413)

Vulnerability from cvelistv5 – Published: 2026-04-08 19:41 – Updated: 2026-04-22 15:28
VLAI
Title
LightRAG has a JWT Algorithm Confusion Vulnerability in LightRAG API
Summary
LightRAG provides simple and fast retrieval-augmented generation. Prior to 1.4.14, the LightRAG API is vulnerable to a JWT algorithm confusion attack where an attacker can forge tokens by specifying 'alg': 'none' in the JWT header. Since the jwt.decode() call does not explicitly deny the 'none' algorithm, a crafted token without a signature will be accepted as valid, leading to unauthorized access. This vulnerability is fixed in 1.4.14.
Severity
4.2 (Medium)
CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:H/I:N/A:N
SSVC
Exploitation: poc Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-04-08 20:18 UTC
CWE
  • CWE-347 - Improper Verification of Cryptographic Signature
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7637 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
HKUDS LightRAG Affected: < 1.4.14
guessed Create a notification for this product.
Show details on NVD website
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