EUVD-2026-20899

fast-jwt has a ReDoS when using RegExp in allowed leading to CPU exhaustion during token verification...

@albirex/platformatic-logto (>=1.0.0, <=3.1.2), @aoi-js/server (>=1.2.3, <=1.2.11) +115 more potentially affected by CVE-2026-35041 via fast-jwt (>=5.0.0, <=6.0.1)

fast-jwt NPM version =5.0.0, =1.0.0, =1.2.3, =1.0.6, =1.0.11, =1.9.4, =0.16.13, =0.16.13, =2.0.5, =5.0.1, =1.0.6, =9.0.2, =0.4.15, =0.10.0, =1.0.1-beta.3, =1.10.1-beta.0 and more Source cves: CVE-2026-35041 Source advisory: OSV:GHSA-CJW9-GHJ4-FWXF...

@jsprismarine/client (>=0.12.2-unstable-20250320195345, <=0.13.1), @jsprismarine/prismarine (>=0.12.2-unstable-20250320195345, <=0.13.1) +1 more potentially affected by CVE-2026-35040 via fast-jwt (>=6.0.0, <=6.0.1)

fast-jwt NPM version =6.0.0, =0.12.2-unstable-20250320195345, =0.12.2-unstable-20250320195345, =0.12.2-unstable-20250320195345, =0.13.1 Source cves: CVE-2026-35040 Source advisory: SNYK:JS-FASTJWT-15965926...

GHSA-3J8V-CGW4-2G6Q fast-jwt: Stateful RegExp (/g or /y) causes non-deterministic allowed-claim validation (logical DoS)

Impact Using certain modifiers on RegExp objects in the allowedAud, allowedIss, allowedSub, allowedJti, or allowedNonce options in verify functions can cause certain unintended behaviours. This is because some modifiers are stateful and will cause failures in every second verification attempt...

@jsprismarine/client (>=0.12.2-unstable-20250320195345, <=0.13.1), @jsprismarine/prismarine (>=0.12.2-unstable-20250320195345, <=0.13.1) +1 more potentially affected by CVE-2026-35040 via fast-jwt (>=6.0.0, <=6.0.1)

fast-jwt NPM version =6.0.0, =0.12.2-unstable-20250320195345, =0.12.2-unstable-20250320195345, =0.12.2-unstable-20250320195345, =0.13.1 Source cves: CVE-2026-35040 Source advisory: OSV:GHSA-3J8V-CGW4-2G6Q...

Incorrect Regular Expression

Overview fast-jwt is a Fast JSON Web Token implementation Affected versions of this package are vulnerable to Incorrect Regular Expression in the allowedAud, allowedIss, allowedSub, allowedJti, or allowedNonce options when used with RegExp objects and RegExp is configured with modifiers such as /...

CVE-2026-35041

fast-jwt provides fast JSON Web Token JWT implementation. From 5.0.0 to 6.2.0, a denial-of-service condition exists in fast-jwt when the allowedAud verification option is configured using a regular expression. Because the aud claim is attacker-controlled and the library evaluates it against the...

CVE-2026-35041 ReDoS in fast-jwt when using RegExp in allowed* leading to CPU exhaustion during token verification

fast-jwt provides fast JSON Web Token JWT implementation. From 5.0.0 to 6.2.0, a denial-of-service condition exists in fast-jwt when the allowedAud verification option is configured using a regular expression. Because the aud claim is attacker-controlled and the library evaluates it against the...

CVE-2026-35041 ReDoS in fast-jwt when using RegExp in allowed* leading to CPU exhaustion during token verification

fast-jwt provides fast JSON Web Token JWT implementation. From 5.0.0 to 6.2.0, a denial-of-service condition exists in fast-jwt when the allowedAud verification option is configured using a regular expression. Because the aud claim is attacker-controlled and the library evaluates it against the...

CVE-2026-35041

The CVE affects fast-jwt versions 5.0.0 through 6.2.0 where allowedAud verification uses a RegExp. The attacker-controlled aud claim, when matched against the provided RegExp, can trigger catastrophic backtracking in the JavaScript engine, causing CPU exhaustion during token verification. This vu...

CVE-2026-35041

fast-jwt provides fast JSON Web Token JWT implementation. From 5.0.0 to 6.2.0, a denial-of-service condition exists in fast-jwt when the allowedAud verification option is configured using a regular expression. Because the aud claim is attacker-controlled and the library evaluates it against the...

CVE-2026-35040

fast-jwt provides fast JSON Web Token JWT implementation. Prior to 6.2.1, using certain modifiers on RegExp objects in the allowedAud, allowedIss, allowedSub, allowedJti, or allowedNonce options in verify functions can cause certain unintended behaviours. This is because some modifiers are statef...

CVE-2026-35040 fast-jwt: Stateful RegExp (/g or /y) causes non-deterministic allowed-claim validation (logical DoS)

fast-jwt provides fast JSON Web Token JWT implementation. Prior to 6.2.1, using certain modifiers on RegExp objects in the allowedAud, allowedIss, allowedSub, allowedJti, or allowedNonce options in verify functions can cause certain unintended behaviours. This is because some modifiers are statef...

CVE-2026-35040 fast-jwt: Stateful RegExp (/g or /y) causes non-deterministic allowed-claim validation (logical DoS)

fast-jwt provides fast JSON Web Token JWT implementation. Prior to 6.2.1, using certain modifiers on RegExp objects in the allowedAud, allowedIss, allowedSub, allowedJti, or allowedNonce options in verify functions can cause certain unintended behaviours. This is because some modifiers are statef...

CVE-2026-35040 fast-jwt: Stateful RegExp (/g or /y) causes non-deterministic allowed-claim validation (logical DoS)

fast-jwt provides fast JSON Web Token JWT implementation. Prior to 6.2.1, using certain modifiers on RegExp objects in the allowedAud, allowedIss, allowedSub, allowedJti, or allowedNonce options in verify functions can cause certain unintended behaviours. This is because some modifiers are statef...

CVE-2026-35040

creationtimestamp| type| source ---|---|--- 2026-04-09 12:50:48+00:00| published-proof-of-concept| https://github.com/nearform/fast-jwt/security/advisories/GHSA-3j8v-cgw4-2g6q...

PT-2026-31622

fast-jwt provides fast JSON Web Token JWT implementation. From 5.0.0 to 6.2.0, a denial-of-service condition exists in fast-jwt when the allowedAud verification option is configured using a regular expression. Because the aud claim is attacker-controlled and the library evaluates it against the...

fast-jwt 安全漏洞

fast-jwt is a JSON Web Token implementation open-sourced by Nearform. Versions of fast-jwt up to 6.2.0 contained security vulnerabilities. These vulnerabilities occurred when the allowedAud verification option used regular expressions, and if the aud declaration controlled by the attacker trigger...

PT-2026-31621

fast-jwt provides fast JSON Web Token JWT implementation. Prior to 6.2.1, using certain modifiers on RegExp objects in the allowedAud, allowedIss, allowedSub, allowedJti, or allowedNonce options in verify functions can cause certain unintended behaviours. This is because some modifiers are statef...

CVE-2026-34950

fast-jwt provides fast JSON Web Token JWT implementation. In 6.1.0 and earlier, the publicKeyPemMatcher regex in fast-jwt/src/crypto.js uses a ^ anchor that is defeated by any leading whitespace in the key string, re-enabling the exact same JWT algorithm confusion attack that CVE-2023-48223 patch...