Vulnerability Description
A race condition existed in the snapd 2.54.2 snap-confine binary when preparing a private mount namespace for a snap. This could allow a local attacker to gain root privileges by bind-mounting their own contents inside the snap's private mount namespace and causing snap-confine to execute arbitrary code and hence gain privilege escalation. Fixed in snapd versions 2.54.3+18.04, 2.54.3+20.04 and 2.54.3+21.10.1
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Canonical | Snapd | <= 2.54.2 |
| Canonical | Ubuntu Linux | 18.04 |
| Fedoraproject | Fedora | 34 |
| Debian | Debian Linux | 10.0 |
Related Weaknesses (CWE)
References
- http://packetstormsecurity.com/files/170176/snap-confine-must_mkdir_and_open_witExploitThird Party AdvisoryVDB Entry
- http://seclists.org/fulldisclosure/2022/Dec/4ExploitMailing ListThird Party Advisory
- http://www.openwall.com/lists/oss-security/2022/02/18/2Mailing ListThird Party Advisory
- http://www.openwall.com/lists/oss-security/2022/02/23/1ExploitMailing ListThird Party Advisory
- http://www.openwall.com/lists/oss-security/2022/02/23/2Mailing ListThird Party Advisory
- http://www.openwall.com/lists/oss-security/2022/11/30/2ExploitMailing ListThird Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedorapro
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedorapro
- https://ubuntu.com/security/notices/USN-5292-1PatchVendor Advisory
- https://www.debian.org/security/2022/dsa-5080Issue TrackingThird Party Advisory
- http://packetstormsecurity.com/files/170176/snap-confine-must_mkdir_and_open_witExploitThird Party AdvisoryVDB Entry
- http://seclists.org/fulldisclosure/2022/Dec/4ExploitMailing ListThird Party Advisory
- http://www.openwall.com/lists/oss-security/2022/02/18/2Mailing ListThird Party Advisory
- http://www.openwall.com/lists/oss-security/2022/02/23/1ExploitMailing ListThird Party Advisory
- http://www.openwall.com/lists/oss-security/2022/02/23/2Mailing ListThird Party Advisory
FAQ
What is CVE-2021-44731?
CVE-2021-44731 is a vulnerability with a CVSS score of 7.8 (HIGH). A race condition existed in the snapd 2.54.2 snap-confine binary when preparing a private mount namespace for a snap. This could allow a local attacker to gain root privileges by bind-mounting their o...
How severe is CVE-2021-44731?
CVE-2021-44731 has been rated HIGH with a CVSS base score of 7.8/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2021-44731?
Check the references section above for vendor advisories and patch information. Affected products include: Canonical Snapd, Canonical Ubuntu Linux, Fedoraproject Fedora, Debian Debian Linux.