CVE Tools

CVE-2024-54150

Algorithm Confusion Vulnerability in cjwt

No known exploitation. EPSS puts it in the 31st percentile. A vendor fix is available.

Published Updated Sources: CVE.org, NVD, BDU

What to do

The vendor has published a fix. Version details are below where the sources state them.

  • Xmidt-org CjwtAffected: < 2.3.0Upgrade to: not statedStated by: CVE record
  • Сообщество свободного программного обеспечения cjwtAffected: 2.2.0Upgrade to: not statedStated by: BDU

Versions as the sources state them. Full version matrix after sign-in

What it is

From the CVE record

cjwt is a C JSON Web Token (JWT) Implementation. Algorithm confusion occurs when a system improperly verifies the type of signature used, allowing attackers to exploit the lack of distinction between signing methods. If the system doesn't differentiate between an HMAC signed token and an RS/EC/PS signed token during verification, it becomes vulnerable to this kind of attack. For instance, an attacker could craft a token with the alg field set to "HS256" while the server expects an asymmetric algorithm like "RS256". The server might mistakenly use the wrong verification method, such as using a public key as the HMAC secret, leading to unauthorised access. For RSA, the key can be computed from a few signatures. For Elliptic Curve (EC), two potential keys can be recovered from one signature. This can be used to bypass the signature mechanism if an application relies on asymmetrically signed tokens. This issue has been addressed in version 2.3.0 and all users are advised to upgrade. There are no known workarounds for this vulnerability.

In plain language

No plain-language summary for this CVE yet.

Exploitation

Where each signal puts this CVE on the scale from published to confirmed exploited.

EPSS31st
CISA KEV

Not in the catalog. CISA has not confirmed exploitation.

Public exploits

No public exploit or proof of concept found in the sources we track.

EPSS

0.4% chance of exploitation activity in the next 30 days, which ranks it in the 31st percentile of scored CVEs.

Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.

Lifecycle

5 events over 1 day, from the signal feeds we watch.

  1. Patch availablerecord updated
  2. Publishedweakness classified, att&ck mapped

Affected products

Technical detail

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

Scored 9.1 by NVD.

How it is reached

  • Attack Vector NetworkExploitable remotely over the network without any special conditions
  • Attack Complexity LowNo special conditions — the attack can be reliably reproduced
  • Privileges Required NoneNo authentication required — anyone can exploit this
  • User Interaction NoneNo user interaction needed — fully automated exploitation

Scope

  • Scope UnchangedImpact is limited to the vulnerable component itself

Impact if exploited

  • Confidentiality HighTotal information disclosure — all data in the component is compromised
  • Integrity HighTotal loss of integrity — attacker can modify any data in the component
  • Availability NoneNo availability impact

Weaknesses

ATT&CK techniques

Mapped from the weaknesses above (CWE to ATT&CK), not observed in attacks.

Sources

Watch the software you run.

My Stack ranks new CVEs for your products by real-world exploitation, so the next serious one reaches you without reading every advisory.

We'll flag the next CVE, public exploit or patch for Cjwt, not every advisory.