@jsprismarine/client (>=0.1.0-rc.50, <=0.14.2), @jsprismarine/prismarine (>=0.12.2-unstable-20250320195345, <=0.14.2) +2 more potentially affected by CVE-2026-107719 via fast-jwt (>=6.0.0, <=6.3.3)

fast-jwt NPM version =6.0.0, =0.1.0-rc.50, =0.12.2-unstable-20250320195345, =0.1.0-rc.50, =0.1.0-rc.50, =0.1.0-rc.52 Source cves: CVE-2026-107719 Source advisory: SNYK:JS-FASTJWT-20825051...

GHSA-X937-HJ6V-793P fast-jwt: Verifier cache accepts expired JWTs without iat.

Summary cacheSet only derives its exp cache deadline inside hasIat src/verifier.js:127-140. JWT iat is optional. For a valid token with exp but no iat, cacheSet substitutes clockTimestamp + clockTolerance + cacheTTL src/verifier.js:142-146. Later, the cache path returns the saved payload before...

Insufficient Session Expiration

Overview fast-jwt is a Fast JSON Web Token implementation Affected versions of this package are vulnerable to Insufficient Session Expiration via the verifier cache in src/verifier.js, where the cacheSet function only derived exp and nbf bounds from a token's payload when the iat claim was also...

NPM: fast-jwt: createVerifier accepts unsigned JWTs when key is '' or null and algorithms is explicitly set

NPM: fast-jwt: createVerifier accepts unsigned JWTs when key is '' or null and algorithms is explicitly set vulnerability discovered by ? in WordPress Npm fast-jwt versions = 6.3.0...

fast-jwt: createVerifier accepts unsigned JWTs when key is '' or null and algorithms is explicitly set

Summary createVerifier in fast-jwt ≤ 6.3.0 skips signature verification entirely when the key option is a falsy synchronous value '' or null and the algorithms option is set to a non-empty allowlist. An attacker who can present a JWT to the application — regardless of algorithm — can forge...

@jsprismarine/client (>=0.12.2-unstable-20250320195345, <=0.14.1), @jsprismarine/prismarine (>=0.12.2-unstable-20250320195345, <=0.14.1) +1 more potentially affected by CVE-2026-107720 via fast-jwt (>=6.0.0, <=6.2.4)

fast-jwt NPM version =6.0.0, =0.12.2-unstable-20250320195345, =0.12.2-unstable-20250320195345, =0.12.2-unstable-20250320195345, =0.14.1 Source cves: CVE-2026-107720 Source advisory: SNYK:JS-FASTJWT-20825050...

@jsprismarine/client (>=0.12.2-unstable-20250320195345, <=0.14.1), @jsprismarine/prismarine (>=0.12.2-unstable-20250320195345, <=0.14.1) +1 more potentially affected by CVE-2026-107720 via fast-jwt (>=6.0.0, <=6.2.4)

fast-jwt NPM version =6.0.0, =0.12.2-unstable-20250320195345, =0.12.2-unstable-20250320195345, =0.12.2-unstable-20250320195345, =0.14.1 Source cves: CVE-2026-107720 Source advisory: OSV:GHSA-8WPC-H4Q6-8FXV...

@jsprismarine/client (>=0.12.2-unstable-20250320195345, <=0.14.1), @jsprismarine/prismarine (>=0.12.2-unstable-20250320195345, <=0.14.1) +1 more potentially affected by CVE-2026-107720 via fast-jwt (>=6.0.0, <=6.2.4)

fast-jwt NPM version =6.0.0, =0.12.2-unstable-20250320195345, =0.12.2-unstable-20250320195345, =0.12.2-unstable-20250320195345, =0.14.1 Source cves: CVE-2026-107720 Source advisory: GHSA-8WPC-H4Q6-8FXV...

GHSA-8WPC-H4Q6-8FXV fast-jwt: createVerifier accepts unsigned JWTs when key is '' or null and algorithms is explicitly set

Summary createVerifier in fast-jwt ≤ 6.3.0 skips signature verification entirely when the key option is a falsy synchronous value '' or null and the algorithms option is set to a non-empty allowlist. An attacker who can present a JWT to the application — regardless of algorithm — can forge...

Improper Verification of Cryptographic Signature

Overview fast-jwt is a Fast JSON Web Token implementation Affected versions of this package are vulnerable to Improper Verification of Cryptographic Signature via createVerifier in src/verifier.js, when an empty string or null is passed as the key option. Because the falsy-key branch skipped key...

NPM: fast-jwt: Incomplete patch of CVE-2026-34950: Non-whitespace key-prefix re-enables RSA→HS256 algorithm confusion

NPM: fast-jwt: Incomplete patch of CVE-2026-34950: Non-whitespace key-prefix re-enables RSA→HS256 algorithm confusion vulnerability discovered by ? in WordPress Npm fast-jwt versions = 6.2.0, = 6.2.4...

@jsprismarine/client (>=0.13.5-unstable-20260512190500, <=0.14.1), @jsprismarine/prismarine (>=0.13.5-unstable-20260512190500, <=0.14.1) +1 more potentially affected by CVE-2026-107722 via fast-jwt (6.2.4)

fast-jwt NPM version 6.2.4 is affected by a known vulnerability. The following packages have a transitive dependency on fast-jwt and may be impacted: - @jsprismarine/client =0.13.5-unstable-20260512190500, =0.13.5-unstable-20260512190500, =0.13.5-unstable-20260512190500, =0.14.1 Source cves:...

GHSA-WW5H-9M49-7XX4 fast-jwt: Incomplete patch of CVE-2026-34950: Non-whitespace key-prefix re-enables RSA→HS256 algorithm confusion

Summary The fix for CVE-2026-34950 CVSS 9.1, released in v6.2.0 is incomplete. It adds key.trim to the PEM-detection path in src/crypto.js, but String.prototype.trim only strips characters classified as whitespace by the ECMAScript specification. The subsequent ^-anchored regex /^-----BEGIN?: RSA...

@jsprismarine/client (>=0.13.5-unstable-20260512190500, <=0.14.1), @jsprismarine/prismarine (>=0.13.5-unstable-20260512190500, <=0.14.1) +1 more potentially affected by CVE-2026-107722 via fast-jwt (6.2.4)

fast-jwt NPM version 6.2.4 is affected by a known vulnerability. The following packages have a transitive dependency on fast-jwt and may be impacted: - @jsprismarine/client =0.13.5-unstable-20260512190500, =0.13.5-unstable-20260512190500, =0.13.5-unstable-20260512190500, =0.14.1 Source cves:...

@jsprismarine/client (>=0.13.5-unstable-20260512190500, <=0.14.1), @jsprismarine/prismarine (>=0.13.5-unstable-20260512190500, <=0.14.1) +1 more potentially affected by CVE-2026-107722 +1 more via fast-jwt (6.2.4)

fast-jwt NPM version 6.2.4 is affected by a known vulnerability. The following packages have a transitive dependency on fast-jwt and may be impacted: - @jsprismarine/client =0.13.5-unstable-20260512190500, =0.13.5-unstable-20260512190500, =0.13.5-unstable-20260512190500, =0.14.1 Source cves:...

fast-jwt: Incomplete patch of CVE-2026-34950: Non-whitespace key-prefix re-enables RSA→HS256 algorithm confusion

Summary The fix for CVE-2026-34950 CVSS 9.1, released in v6.2.0 is incomplete. It adds key.trim to the PEM-detection path in src/crypto.js, but String.prototype.trim only strips characters classified as whitespace by the ECMAScript specification. The subsequent ^-anchored regex /^-----BEGIN?: RSA...

Improper Verification of Cryptographic Signature

Overview fast-jwt is a Fast JSON Web Token implementation Affected versions of this package are vulnerable to Improper Verification of Cryptographic Signature via the key-type detection logic in src/crypto.js, where a non-whitespace prefix control characters, zero-width Unicode, comments, HTTP/PG...

NPM: fast-jwt clockTolerance: Infinity silently bypasses both exp and nbf validation (and persists in the verifier cache)

NPM: fast-jwt clockTolerance: Infinity silently bypasses both exp and nbf validation and persists in the verifier cache vulnerability discovered by ? in WordPress Npm fast-jwt versions = 6.2.4...

@jsprismarine/client (>=0.12.2-unstable-20250320195345, <=0.14.1), @jsprismarine/prismarine (>=0.12.2-unstable-20250320195345, <=0.14.1) +1 more potentially affected by CVE-2026-107721 via fast-jwt (>=6.0.0, <=6.2.4)

fast-jwt NPM version =6.0.0, =0.12.2-unstable-20250320195345, =0.12.2-unstable-20250320195345, =0.12.2-unstable-20250320195345, =0.14.1 Source cves: CVE-2026-107721 Source advisory: SNYK:JS-FASTJWT-20825053...

@jsprismarine/client (>=0.12.2-unstable-20250320195345, <=0.14.1), @jsprismarine/prismarine (>=0.12.2-unstable-20250320195345, <=0.14.1) +1 more potentially affected by CVE-2026-107721 via fast-jwt (>=6.0.0, <=6.2.4)

fast-jwt NPM version =6.0.0, =0.12.2-unstable-20250320195345, =0.12.2-unstable-20250320195345, =0.12.2-unstable-20250320195345, =0.14.1 Source cves: CVE-2026-107721 Source advisory: OSV:GHSA-687G-22H4-J4W4...