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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
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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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.


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Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.