CVE-2026-54430

liboauth2 is vulnerable to Server-Side Request Forgery in oauth2_jose_jwks_aws_alb_resolve() function. The AWS ALB verifier reads both signer and kid from the unverified JWT header. If signer matches the configured ARN, kid is appended to alb_base_url without URL encoding or path sanitization, and the HTTP GET is issued before signature verification. This allows an attacker to force the server to send a GET request to an attacker-chosen internal path. This issue was fixed in version 2.3.0

CVSS

No CVSS.

References

Link	Resource
https://cert.pl/en/posts/2026/07/CVE-2026-54430
https://github.com/OpenIDC/liboauth2
https://github.com/OpenIDC/liboauth2/commit/347507ac5b51f48c2933bbe49b2ee07c2af4712b

Configurations

No configuration.

History

02 Jul 2026, 12:17

Type	Values Removed	Values Added
References	~~{'url': 'https://cert.pl/en/posts/2026/06/CVE-2026-54430', 'source': 'cvd@cert.pl'}~~	() https://cert.pl/en/posts/2026/07/CVE-2026-54430 -

02 Jul 2026, 11:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-02 11:16

Updated : 2026-07-02 17:43

NVD link : CVE-2026-54430

Mitre link : CVE-2026-54430

CVE.ORG link : CVE-2026-54430

JSON object : View

Products Affected

No product.

CWE

CWE-918

Server-Side Request Forgery (SSRF)

{"id": "CVE-2026-54430", "cveTags": [], "metrics": {"ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-54430", "role": "CISA Coordinator", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "version": "2.0.3", "timestamp": "2026-07-02T12:17:15.414798Z"}}], "cvssMetricV40": [{"type": "Secondary", "source": "cvd@cert.pl", "cvssData": {"Safety": "NOT_DEFINED", "version": "4.0", "Recovery": "NOT_DEFINED", "baseScore": 5.1, "Automatable": "NOT_DEFINED", "attackVector": "LOCAL", "baseSeverity": "MEDIUM", "valueDensity": "NOT_DEFINED", "vectorString": "CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:L/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X", "exploitMaturity": "NOT_DEFINED", "providerUrgency": "NOT_DEFINED", "userInteraction": "NONE", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "NONE", "subIntegrityImpact": "NONE", "vulnIntegrityImpact": "LOW", "integrityRequirement": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "subAvailabilityImpact": "NONE", "vulnAvailabilityImpact": "NONE", "availabilityRequirement": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "subConfidentialityImpact": "LOW", "vulnConfidentialityImpact": "NONE", "confidentialityRequirement": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "vulnerabilityResponseEffort": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED"}}]}, "affected": [{"source": "cvd@cert.pl", "affectedData": [{"repo": "https://github.com/OpenIDC/liboauth2", "vendor": "OpenIDC", "modules": ["oauth2_jose_jwks_aws_alb_resolve()"], "product": "liboauth2", "versions": [{"status": "affected", "version": "0", "lessThan": "2.3.0", "versionType": "semver"}], "programFiles": ["src/jose.c"], "defaultStatus": "unaffected"}]}], "published": "2026-07-02T11:16:16.423", "references": [{"url": "https://cert.pl/en/posts/2026/07/CVE-2026-54430", "source": "cvd@cert.pl"}, {"url": "https://github.com/OpenIDC/liboauth2", "source": "cvd@cert.pl"}, {"url": "https://github.com/OpenIDC/liboauth2/commit/347507ac5b51f48c2933bbe49b2ee07c2af4712b", "source": "cvd@cert.pl"}], "vulnStatus": "Deferred", "weaknesses": [{"type": "Secondary", "source": "cvd@cert.pl", "description": [{"lang": "en", "value": "CWE-918"}]}], "descriptions": [{"lang": "en", "value": "liboauth2 is vulnerable to Server-Side Request Forgery in\u00a0oauth2_jose_jwks_aws_alb_resolve() function.\u00a0The AWS ALB verifier reads both signer and kid from the unverified JWT\nheader. If signer matches the configured ARN, kid is appended to\nalb_base_url without URL encoding or path sanitization, and the HTTP GET\nis issued before signature verification. This allows an attacker to force\nthe server to send a GET request to an attacker-chosen internal path.\n\nThis issue was fixed in version 2.3.0"}], "lastModified": "2026-07-02T17:43:14.020", "sourceIdentifier": "cvd@cert.pl"}