Security update for python-PyJWT
This security update addresses multiple vulnerabilities in python-PyJWT, including SSRF and token forgery via PyJWKClient, algorithm allow-list bypass during JWT decoding, unbounded JWKS endpoint requests causing DoS, unbounded Base64URL decoding leading to DoS, and forged HS256 tokens due to lack of validation of JSON Web Keys in HMAC algorithms.
AI Analysis
Technical Summary
The update for python-PyJWT fixes five distinct security issues: CVE-2026-48522 involves PyJWKClient passing URI arguments directly to urllib.request.urlopen(), enabling SSRF and token forgery. CVE-2026-48523 allows bypassing the verifier-side algorithm allow-list when decoding JWTs with a PyJWK key. CVE-2026-48524 causes unbounded JWKS endpoint requests due to unlimited processing of JWTs with unknown kid values, leading to denial of service. CVE-2026-48525 permits denial of service through unbounded Base64URL decoding of an unused payload segment in detached JWS with b64=false. CVE-2026-48526 allows forged HS256 tokens because of missing validation of JSON Web Keys usage in HMAC algorithms during JWT decoding.
Potential Impact
These vulnerabilities collectively impact the security of JWT processing in python-PyJWT, potentially allowing attackers to perform server-side request forgery, bypass algorithm restrictions, cause denial of service through resource exhaustion, and forge tokens. This compromises authentication integrity and availability of services relying on PyJWT for JWT validation.
Mitigation Recommendations
A security update has been released to address these vulnerabilities. Users should apply the official patch or update python-PyJWT to the fixed version as provided by the vendor or distribution. No additional mitigations are specified beyond applying the update.
Security update for python-PyJWT
Description
This security update addresses multiple vulnerabilities in python-PyJWT, including SSRF and token forgery via PyJWKClient, algorithm allow-list bypass during JWT decoding, unbounded JWKS endpoint requests causing DoS, unbounded Base64URL decoding leading to DoS, and forged HS256 tokens due to lack of validation of JSON Web Keys in HMAC algorithms.
Affected software
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The update for python-PyJWT fixes five distinct security issues: CVE-2026-48522 involves PyJWKClient passing URI arguments directly to urllib.request.urlopen(), enabling SSRF and token forgery. CVE-2026-48523 allows bypassing the verifier-side algorithm allow-list when decoding JWTs with a PyJWK key. CVE-2026-48524 causes unbounded JWKS endpoint requests due to unlimited processing of JWTs with unknown kid values, leading to denial of service. CVE-2026-48525 permits denial of service through unbounded Base64URL decoding of an unused payload segment in detached JWS with b64=false. CVE-2026-48526 allows forged HS256 tokens because of missing validation of JSON Web Keys usage in HMAC algorithms during JWT decoding.
Potential Impact
These vulnerabilities collectively impact the security of JWT processing in python-PyJWT, potentially allowing attackers to perform server-side request forgery, bypass algorithm restrictions, cause denial of service through resource exhaustion, and forge tokens. This compromises authentication integrity and availability of services relying on PyJWT for JWT validation.
Mitigation Recommendations
A security update has been released to address these vulnerabilities. Users should apply the official patch or update python-PyJWT to the fixed version as provided by the vendor or distribution. No additional mitigations are specified beyond applying the update.
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_security_advisory
- Csaf Version
- 2.0
- Publisher
- SUSE Product Security Team
- Advisory Id
- openSUSE-SU-2026:21095-1
- Cve Count
- 5
- Additional Cves
- ["CVE-2026-48523","CVE-2026-48524","CVE-2026-48525","CVE-2026-48526"]
- State
- PUBLISHED
Threat ID: 6aab497855bf5e2cf5990e3f
Added to database: 09/17/2026, 01:59:20 UTC
Last enriched: 09/17/2026, 02:18:18 UTC
Last updated: 09/17/2026, 02:18:18 UTC
Views: 2
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