CVE-2024-37568Public exploitNetwork attack vector

Token forgery via asymmetric-key algorithm confusion

Published Jun 9, 2024 · Updated Nov 3, 2025

JWT signature verification in Authlib before 1.3.1 allows remote attackers to forge tokens by substituting HMAC for an asymmetric algorithm. When jwt.decode receives no algorithm allowlist, OctKey.import_key accepts a PEM or SSH public key as an HMAC secret and trusts the token's alg header. An application must decode attacker-supplied JWTs without specifying algorithms; accepted forged claims can bypass authentication or authorization.

CVSS severity7.5
High
EPSS probability0.38%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

JWT signature verification in Authlib before 1.3.1 allows remote attackers to forge tokens by substituting HMAC for an asymmetric algorithm. When jwt.decode receives no algorithm allowlist, OctKey.import_key accepts a PEM or SSH public key as an HMAC secret and trusts the token's alg header. An application must decode attacker-supplied JWTs without specifying algorithms; accepted forged claims can bypass authentication or authorization.

The record

CVE
CVE-2024-37568
Published
Jun 9, 2024
Updated
Nov 3, 2025
Vendor
Authlib
Product
Authlib
Classifications
CWE-347, CWE-284, CWE-327, T1606
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 9, 2024CVE publishedPublication date reported by the CVE source.
  2. Nov 3, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <1.3.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Authlib · Authlibversion=0 <1.3.1

Published CVSS scores

7.5National Vulnerability DatabaseCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
7.4GitHub Advisory DatabaseCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
7.5CISA-ADPCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-347Improper Verification of Cryptographic Signature
CWE-284Improper Access Control
CWE-327Use of a Broken or Risky Cryptographic Algorithm
T1606Forge Web Credentials

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo