RPK Server Signature Algorithm Selection Can Dereference a Missing Certificate
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- The rating the maker of the software gives it. Shown when it differs from the CVSS level.What do these mean? →
- Low (openssl)
- Fix
- Fixed in 4.0.2, 3.6.4, 3.5.8, 3.4.7
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
- Exploitation: none
- Automatable: yes
- Technical impact: partial
Summary
Issue summary: In a server or client configuration with RFC7250 Raw Public Keys (RPKs) enabled, and only the private key (with no associated certificate) configured locally, a NULL pointer dereference may occur when the remote peer solicits raw public keys and also sends the typically omitted "signature_algorithms_cert" TLS extension. Impact summary: The impact is limited to a possible Denial of Service as a result of an application abort, no data disclosure or remote command execution are possible. CWE: CWE-476: NULL Pointer Dereference Description: While a passing comment in sample code in the documentation suggests that key-only RPK configurations are supported, the best-practice RPK configuration is to always configure a corresponding certificate (possibly self-signed or signed by any convenient CA). When the private key is configured along with a matching certificate, the "signature_algorithms_cert" extension is handled reliably even without the fix, and peer clients or servers that don't support raw public keys may be able to complete a TLS connection by pinning or verifying the corresponding certificate or its public key. Deployments that prefer to configure just a private key with no certificate need to upgrade to an updated release as noted below. FIPS impact: no No FIPS modules are affected by this issue, as the SSL protocol implementation is outside the OpenSSL FIPS module boundary.
Timeline
- CVE published
- CISA SSVC assessment
Exploitation: none · Automatable: yes · Technical impact: partial
- Record last updated
Affected versions
- OpenSSL OpenSSL
From 4.0.0 · fixed in 4.0.2; From 3.6.0 · fixed in 3.6.4; From 3.5.0 · fixed in 3.5.8; From 3.4.0 · fixed in 3.4.7