CVE-2023-37464
Incorrect Authentication Tag length usage in AES GCM decryption in OpenIDC/cjose
Public exploit available. Not confirmed exploited in the wild yet. A vendor fix is available.
What to do
The vendor has published a fix. Version details are below where the sources state them.
What it is
From the CVE record
OpenIDC/cjose is a C library implementing the Javascript Object Signing and Encryption (JOSE). The AES GCM decryption routine incorrectly uses the Tag length from the actual Authentication Tag provided in the JWE. The spec says that a fixed length of 16 octets must be applied. Therefore this bug allows an attacker to provide a truncated Authentication Tag and to modify the JWE accordingly. Users should upgrade to a version >= 0.6.2.2. Users unable to upgrade should avoid using AES GCM encryption and replace it with another encryption algorithm (e.g. AES CBC).
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.
- CISA KEV
Not in the catalog. CISA has not confirmed exploitation.
- Public exploits
1 source with a proof of concept or module.
Exploit links, PoCs and Metasploit modules after sign-in- EPSS
0.7% chance of exploitation activity in the next 30 days, which ranks it in the 51st percentile of scored CVEs.
Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.
Lifecycle
The patch came 471 days before any public exploit.
- OpenVAS check added
- Public exploit / PoCsource: github-poc
- Patch availablerecord updated
- Publishedweakness classified, att&ck mapped
Affected products
Technical detail
CVSS 3.1 vector
Open in the CVSS calculatorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:N
Scored 8.6 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 ChangedThe exploit can affect other components (e.g. sandbox escape, host compromise from VM)
Impact if exploited
- Confidentiality NoneNo confidentiality impact
- 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
References in the record
- datatracker.ietf.org/doc/html/rfc7518
- github.com/OpenIDC/cjose/commit/7325e9a5e71e2fc0e350487ecac7d84acdf0ed5e
- github.com/OpenIDC/cjose/releases/tag/v0.6.2.2
And 6 more references. See all after sign-in
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