memfd: deny writeable mappings when implying SEAL_WRITE
- 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- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean?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 6.6.143, 6.12.93, 6.18.35, 7.0.12
- 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: no
- Technical impact: total
Summary
In the Linux kernel, the following vulnerability has been resolved: memfd: deny writeable mappings when implying SEAL_WRITE When SEAL_EXEC is added, SEAL_WRITE is implied to make W^X. But the implied seal is set after the check that makes sure the memfd can not have any writable mappings. This means one can use SEAL_EXEC to apply SEAL_WRITE while having writeable mappings. This breaks the contract that SEAL_WRITE provides and can be used by an attacker to pass a memfd that appears to be write sealed but can still be modified arbitrarily. Fix this by adding the implied seals before the call for mapping_deny_writable() is done.
Timeline
- CVE published
- CISA SSVC assessment
Exploitation: none · Automatable: no · Technical impact: total
- Record last updated
Affected versions
- Linux Linux
From c4f75bc8bd6b3d62665e1f5400c419540edb5601 · fixed in b3f4f82d1315f1439059a83d1c22c51a5b43d99e; From c4f75bc8bd6b3d62665e1f5400c419540edb5601 · fixed in 3be2a24f7f72ad7321ed6ad1715b956a4527bcf4; From c4f75bc8bd6b3d62665e1f5400c419540edb5601 · fixed in 0995d1f79aed8ccbf62056189dd53fd19726ea08; From c4f75bc8bd6b3d62665e1f5400c419540edb5601 · fixed in 555702282d4536a865dfffb1cd4f6028f196e7e8; From c4f75bc8bd6b3d62665e1f5400c419540edb5601 · fixed in 3b041514cb6eae45869b020f743c14d983363222
- Linux Linux
6.3
- KernelLinux
From 6.3.0 · fixed in 6.6.143; From 6.7.0 · fixed in 6.12.93; From 6.13.0 · fixed in 6.18.35; From 6.19.0 · fixed in 7.0.12