USN-8916-1
pyjwt vulnerabilities
Published Oct 13, 2026 · updated Oct 14, 2026
YuSung Han discovered that PyJWT did not properly validate certain JWK keys when performing HMAC verification. An attacker could possibly use this issue to forge authentication tokens. This issue only affected Ubuntu 26.04 LTS. (CVE-2026-102266) Rohan Das discovered that PyJWT incorrectly handled redirects when fetching key sets. A remote attacker could possibly use this issue to cause PyJWT to disclose sensitive information. This issue only affected Ubuntu 22.04 LTS, Ubuntu 24.04 LTS, Ubuntu 26.04 LTS. (CVE-2026-102267) It was discovered that PyJWT incorrectly recognized certain PEM representations. An attacker who knew the public key could possibly use this issue to forge authentication tokens. This issue only affected Ubuntu 18.04 LTS, Ubuntu 20.04 LTS, Ubuntu 22.04 LTS, Ubuntu 24.04 LTS, Ubuntu 26.04 LTS. (CVE-2026-102268) Nuno Lopes discovered that PyJWT incorrectly handled DER public keys when performing HMAC verification. An attacker who knew the public key could possibly use this issue to forge authentication tokens. (CVE-2026-102271) It was discovered that PyJWT did not properly handle certain JWK keys prefixed with a byte-order mark. An attacker who knew the public key could possibly use this issue to forge authentication tokens. (CVE-2026-102272) Charles Vosburgh discovered that PyJWT incorrectly handled certain JWK containers when performing HMAC verification. An attacker who knew the public key could possibly use this issue to forge authentication tokens. (CVE-2026-102273)
Timeline
Detection, updates, and resolution for this record.
Oct 13, 2026 · OSV.dev
Detected
YuSung Han discovered that PyJWT did not properly validate certain JWK keys when performing HMAC verification. An attacker could possibly use this issue to forge authentication tokens. This issue only affected Ubuntu 26.04 LTS. (CVE-2026-102266) Rohan Das discovered that PyJWT incorrectly handled redirects when fetching key sets. A remote attacker could possibly use this issue to cause PyJWT to di
Oct 14, 2026 · OSV.dev
Fix available
pyjwt fixed in 1.3.0-1ubuntu0.1+esm3; pyjwt fixed in 1.5.3+ds1-1ubuntu0.1+esm3; pyjwt fixed in 1.7.1-2ubuntu2.1+esm3; pyjwt fixed in 2.3.0-1ubuntu0.5
Oct 14, 2026 · OSV.dev
Fix available
pyjwt fixed in 1.3.0-1ubuntu0.1+esm3
Oct 14, 2026 · OSV.dev
Fix available
pyjwt fixed in 1.5.3+ds1-1ubuntu0.1+esm3
Oct 14, 2026 · OSV.dev
Fix available
pyjwt fixed in 1.7.1-2ubuntu2.1+esm3
Oct 14, 2026 · OSV.dev
Fix available
pyjwt fixed in 2.3.0-1ubuntu0.5
Oct 14, 2026 · OSV.dev
Fix available
pyjwt fixed in 2.7.0-1ubuntu0.3
Oct 14, 2026 · OSV.dev
Fix available
pyjwt fixed in 2.10.1-4ubuntu1.2
Oct 14, 2026 · OSV.dev
Updated
YuSung Han discovered that PyJWT did not properly validate certain JWK keys when performing HMAC verification. An attacker could possibly use this issue to forge authentication tokens. This issue only affected Ubuntu 26.04 LTS. (CVE-2026-102266) Rohan Das discovered that PyJWT incorrectly handled redirects when fetching key sets. A remote attacker could possibly use this issue to cause PyJWT to di
Affected
- Ubuntu:22.04:LTS pyjwt0 → 2.3.0-1ubuntu0.5
- Ubuntu:24.04:LTS pyjwt0 → 2.7.0-1ubuntu0.3
- Ubuntu:26.04:LTS pyjwt0 → 2.10.1-4ubuntu1.2
- Ubuntu:Pro:16.04:LTS pyjwt0 → 1.3.0-1ubuntu0.1+esm3
- Ubuntu:Pro:18.04:LTS pyjwt0 → 1.5.3+ds1-1ubuntu0.1+esm3
- Ubuntu:Pro:20.04:LTS pyjwt0 → 1.7.1-2ubuntu2.1+esm3