High severity · published Feb 8, 2021
CVE-2021-26910
Firejail before 0.9.64.4 allows attackers to bypass intended access restrictions because there is a TOCTOU race condition between a stat operation and an OverlayFS mount operation
7.0
CVSS
0.4%
EPSS
No
On KEV
Description
Firejail before 0.9.64.4 allows attackers to bypass intended access restrictions because there is a TOCTOU race condition between a stat operation and an OverlayFS mount operation.
CVSS vector
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack vector
Local
Complexity
High
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 38% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
DL
Debian Linux · Debian
9.0; 10.0 · source: NVD
FI
Firejail · Firejail Project
before 0.9.64.4 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-26910
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-26910
Exploit
http://www.openwall.com/lists/oss-security/2021/02/09/1
Patch
https://github.com/netblue30/firejail/commit/97d8a03cad19501f017587cc4e47d8418273834b
Release Notes
https://github.com/netblue30/firejail/releases/tag/0.9.64.4
Third Party Advisory
https://lists.debian.org/debian-lts-announce/2021/02/msg00015.html
Third Party Advisory
https://security.gentoo.org/glsa/202105-19
Exploit
https://unparalleled.eu/blog/2021/20210208-rigged-race-against-firejail-for-local-root/
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