FKIE_CVE-2026-81829

Vulnerability from fkie_nvd - Published: 2026-09-17 14:17 - Updated: 2026-09-21 18:17
Severity
5.3 (Medium) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
Summary
A flaw was found in SmallRye JWT's AwsAlbKeyResolver, which is used by applications to verify JSON Web Tokens signed by AWS Application Load Balancers. When the AWS_ALB key provider is configured, the resolver constructs the key-fetch URL by directly concatenating the attacker-controlled kid header value from an inbound JWT without sanitizing path traversal characters or query-string separators. This allows an unauthenticated remote attacker to force the application server to issue GET requests to arbitrary paths on the same origin as the configured key endpoint. As a result, non-public endpoints or internal data reachable on that origin may be read by the attacker before JWT signature verification takes place.
References
secalert@redhat.comhttps://access.redhat.com/errata/RHSA-2026:69470
secalert@redhat.comhttps://access.redhat.com/security/cve/CVE-2026-81829
secalert@redhat.comhttps://bugzilla.redhat.com/show_bug.cgi?id=2524980
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "cpes": [
            "cpe:/a:redhat:exploit_intelligence:0"
          ],
          "defaultStatus": "affected",
          "packageName": "exploit-intelligence/agent-client-rhel9",
          "product": "Exploit Intelligence",
          "vendor": "Red Hat"
        },
        {
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "cpes": [
            "cpe:/a:redhat:apicurio_registry:3"
          ],
          "defaultStatus": "affected",
          "packageName": "quarkus-smallrye-jwt",
          "product": "Red Hat build of Apicurio Registry 3",
          "vendor": "Red Hat"
        },
        {
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "cpes": [
            "cpe:/a:redhat:apicurio_registry:3"
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          "defaultStatus": "unknown",
          "packageName": "smallrye-jwt",
          "product": "Red Hat build of Apicurio Registry 3",
          "vendor": "Red Hat"
        },
        {
          "collectionURL": "https://access.redhat.com/jbossnetwork/restricted/listSoftware.html",
          "cpes": [
            "cpe:/a:redhat:jboss_enterprise_application_platform:8"
          ],
          "defaultStatus": "affected",
          "packageName": "smallrye-jwt",
          "product": "Red Hat JBoss Enterprise Application Platform 8",
          "vendor": "Red Hat"
        },
        {
          "collectionURL": "https://access.redhat.com/jbossnetwork/restricted/listSoftware.html",
          "cpes": [
            "cpe:/a:redhat:jbosseapxp"
          ],
          "defaultStatus": "affected",
          "packageName": "smallrye-jwt",
          "product": "Red Hat JBoss Enterprise Application Platform Expansion Pack",
          "vendor": "Red Hat"
        }
      ],
      "source": "secalert@redhat.com"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "A flaw was found in SmallRye JWT\u0027s AwsAlbKeyResolver, which is used by applications to verify JSON Web Tokens signed by AWS Application Load Balancers. When the AWS_ALB key provider is configured, the resolver constructs the key-fetch URL by directly concatenating the attacker-controlled kid header value from an inbound JWT without sanitizing path traversal characters or query-string separators. This allows an unauthenticated remote attacker to force the application server to issue GET requests to arbitrary paths on the same origin as the configured key endpoint. As a result, non-public endpoints or internal data reachable on that origin may be read by the attacker before JWT signature verification takes place."
    }
  ],
  "id": "CVE-2026-81829",
  "lastModified": "2026-09-21T18:17:11.057",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 5.3,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "LOW",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 1.4,
        "source": "secalert@redhat.com",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-81829",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-09-17T15:45:20.084526Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-09-17T14:17:32.323",
  "references": [
    {
      "source": "secalert@redhat.com",
      "url": "https://access.redhat.com/errata/RHSA-2026:69470"
    },
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    },
    {
      "source": "secalert@redhat.com",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2524980"
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  ],
  "sourceIdentifier": "secalert@redhat.com",
  "vulnStatus": "Awaiting Analysis",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-22"
        }
      ],
      "source": "secalert@redhat.com",
      "type": "Secondary"
    }
  ]
}



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