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CVE-2020-26160

Status: ModifiedHigh (7.5)—PoC
Severity7.5High · CVSS 3.1
Exploitation probability2.16 %higher than 82% of CVEs
Active exploitationNonot in the CISA catalog
Public exploitAvailableProof of concept on GitHub (unverified)

jwt-go before 4.0.0-preview1 allows attackers to bypass intended access restrictions in situations with []string{} for m["aud"] (which is allowed by the specification). Because the type assertion fails, "" is the value of aud. This is a security problem if the JWT token is presented to a service that lacks its own audience check.

CVSS

Base score
7.5
Version
3.1
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days
2.16 %
Percentile among all scored CVEs
82
Score date
10/21/2026

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

Public exploits

Exploit code or detection templates are publicly available. This is not the same as confirmed active exploitation (KEV), but it raises the risk: patch with priority.

⚠️ GitHub proofs of concept are not verified: some are fake or contain malware. Never run them outside an isolated lab.

Affected technologies (1)

Jwt-go Project — Jwt-go

CWEs

References

Show 4 references

Raw JSON (NVD)

Show
{
  "id": "CVE-2020-26160",
  "cveTags": [],
  "metrics": {
    "cvssMetricV2": [
      {
        "type": "Primary",
        "source": "nvd@nist.gov",
        "cvssData": {
          "version": "2.0",
          "baseScore": 5,
          "accessVector": "NETWORK",
          "vectorString": "AV:N/AC:L/Au:N/C:P/I:N/A:N",
          "authentication": "NONE",
          "integrityImpact": "NONE",
          "accessComplexity": "LOW",
          "availabilityImpact": "NONE",
          "confidentialityImpact": "PARTIAL"
        },
        "acInsufInfo": false,
        "impactScore": 2.9,
        "baseSeverity": "MEDIUM",
        "obtainAllPrivilege": false,
        "exploitabilityScore": 10,
        "obtainUserPrivilege": false,
        "obtainOtherPrivilege": false,
        "userInteractionRequired": false
      }
    ],
    "cvssMetricV31": [
      {
        "type": "Secondary",
        "source": "cve@mitre.org",
        "cvssData": {
          "scope": "UNCHANGED",
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          "baseScore": 7.5,
          "attackVector": "NETWORK",
          "baseSeverity": "HIGH",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
          "integrityImpact": "NONE",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "availabilityImpact": "NONE",
          "privilegesRequired": "NONE",
          "confidentialityImpact": "HIGH"
        },
        "impactScore": 3.6,
        "exploitabilityScore": 3.9
      },
      {
        "type": "Primary",
        "source": "nvd@nist.gov",
        "cvssData": {
          "scope": "UNCHANGED",
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          "baseSeverity": "HIGH",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
          "integrityImpact": "NONE",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "availabilityImpact": "NONE",
          "privilegesRequired": "NONE",
          "confidentialityImpact": "HIGH"
        },
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  "affected": [
    {
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      "affectedData": [
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          "product": "n/a",
          "versions": [
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              "version": "n/a"
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  ],
  "published": "2020-09-30T18:15:27.397",
  "references": [
    {
      "url": "https://github.com/dgrijalva/jwt-go/pull/426",
      "tags": [
        "Patch",
        "Third Party Advisory"
      ],
      "source": "cve@mitre.org"
    },
    {
      "url": "https://snyk.io/vuln/SNYK-GOLANG-GITHUBCOMDGRIJALVAJWTGO-596515",
      "tags": [
        "Third Party Advisory"
      ],
      "source": "cve@mitre.org"
    },
    {
      "url": "https://github.com/dgrijalva/jwt-go/pull/426",
      "tags": [
        "Patch",
        "Third Party Advisory"
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      "source": "af854a3a-2127-422b-91ae-364da2661108"
    },
    {
      "url": "https://snyk.io/vuln/SNYK-GOLANG-GITHUBCOMDGRIJALVAJWTGO-596515",
      "tags": [
        "Third Party Advisory"
      ],
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    }
  ],
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "type": "Primary",
      "source": "nvd@nist.gov",
      "description": [
        {
          "lang": "en",
          "value": "CWE-287"
        },
        {
          "lang": "en",
          "value": "CWE-755"
        }
      ]
    }
  ],
  "descriptions": [
    {
      "lang": "en",
      "value": "jwt-go before 4.0.0-preview1 allows attackers to bypass intended access restrictions in situations with []string{} for m[\"aud\"] (which is allowed by the specification). Because the type assertion fails, \"\" is the value of aud. This is a security problem if the JWT token is presented to a service that lacks its own audience check."
    },
    {
      "lang": "es",
      "value": "jwt-go versiones anteriores a 4.0.0-preview1, permite a atacantes omitir las restricciones de acceso previstas en situaciones con []string{} para m[\"aud\"] (que está permitido por la especificación). Porque la aserción de tipo presenta un fallo, \"\" es el valor de aud. Este es un problema de seguridad si el token JWT es presentado para un servicio que carece de su propia comprobación de audiencia"
    }
  ],
  "lastModified": "2026-06-17T03:07:43.907",
  "configurations": [
    {
      "nodes": [
        {
          "negate": false,
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:jwt-go_project:jwt-go:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "68EAFD08-97E3-4FB2-9F63-9A72A9EAFB75",
              "versionEndIncluding": "3.2.0"
            }
          ],
          "operator": "OR"
        }
      ]
    }
  ],
  "sourceIdentifier": "cve@mitre.org"
}