FKIE_CVE-2026-39413

Vulnerability from fkie_nvd - Published: 2026-04-08 20:16 - Updated: 2026-04-22 16:16
Severity ?
4.2 (Medium) - CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:H/I:N/A:N
6.5 (Medium) - CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
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.
References
security-advisories@github.comhttps://github.com/HKUDS/LightRAG/security/advisories/GHSA-8ffj-4hx4-9pgfExploit, Mitigation, Vendor Advisory
af854a3a-2127-422b-91ae-364da2661108https://github.com/github/advisory-database/issues/7373
Impacted products
Vendor Product Version
hkuds lightrag *
To clipboard 

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      "nodes": [
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              "criteria": "cpe:2.3:a:hkuds:lightrag:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "80A2BB57-B14C-4542-8F7F-D0D6F20AFC31",
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      "lang": "en",
      "value": "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 \u0027alg\u0027: \u0027none\u0027 in the JWT header. Since the jwt.decode() call does not explicitly deny the \u0027none\u0027 algorithm, a crafted token without a signature will be accepted as valid, leading to unauthorized access. This vulnerability is fixed in 1.4.14."
    }
  ],
  "id": "CVE-2026-39413",
  "lastModified": "2026-04-22T16:16:58.387",
  "metrics": {
    "cvssMetricV31": [
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        "cvssData": {
          "attackComplexity": "HIGH",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 4.2,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "NONE",
          "privilegesRequired": "HIGH",
          "scope": "UNCHANGED",
          "userInteraction": "REQUIRED",
          "vectorString": "CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:H/I:N/A:N",
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  "published": "2026-04-08T20:16:25.877",
  "references": [
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      "tags": [
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  "vulnStatus": "Modified",
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          "value": "CWE-347"
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}


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  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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