Remote code execution via RPCSEC_GSS packet validation
- 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- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean?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
- Fix
- Fixed in p5, p1, p10, p11
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- 2 proofs of concept on GitHub
- Exploitation: poc
- Automatable: no
- Technical impact: total
Summary
Each RPCSEC_GSS data packet is validated by a routine which checks a signature in the packet. This routine copies a portion of the packet into a stack buffer, but fails to ensure that the buffer is sufficiently large, and a malicious client can trigger a stack overflow. Notably, this does not require the client to authenticate itself first. As kgssapi.ko's RPCSEC_GSS implementation is vulnerable, remote code execution in the kernel is possible by an authenticated user that is able to send packets to the kernel's NFS server while kgssapi.ko is loaded into the kernel. In userspace, applications which have librpcgss_sec loaded and run an RPC server are vulnerable to remote code execution from any client able to send it packets. We are not aware of any such applications in the FreeBSD base system.
Timeline
- CISA SSVC assessment
Exploitation: poc · Automatable: no · Technical impact: total
- CVE published
- Record last updated
Affected versions
- FreeBSD FreeBSD
From 15.0-RELEASE · fixed in p5; From 14.4-RELEASE · fixed in p1; From 14.3-RELEASE · fixed in p10; From 13.5-RELEASE · fixed in p11