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7.8
HIGH CVSS 3.1
CVE-2021-26910
Firejail TOCTOU race condition vulnerability
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.

INFO

Published Date :

Feb. 8, 2021, 8:15 p.m.

Last Modified :

Nov. 21, 2024, 5:57 a.m.

Remotely Exploit :

No

Source :

[email protected]
Affected Products

The following products are affected by CVE-2021-26910 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Debian debian_linux
1 Firejail_project firejail
: Total Affected Vendor : 2 | Products : 2
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 2.0 MEDIUM [email protected]
CVSS 3.1 HIGH [email protected]
CVSS 3.1 HIGH [email protected]
Solution
A Time-of-Check to Time-of-Use (TOCTOU) race condition vulnerability exists in Firejail, which allows attackers to bypass intended access restrictions.
  • Upgrade Firejail to version 0.9.64.4 or later.
  • Update firejail and/or firejail-profiles packages.
Public PoC/Exploit Available at Github

CVE-2021-26910 has a 3 public PoC/Exploit available at Github. Go to the Public Exploits tab to see the list.

References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2021-26910.

URL Resource
http://www.openwall.com/lists/oss-security/2021/02/09/1 Exploit Mailing List Patch Third Party Advisory
https://github.com/netblue30/firejail/commit/97d8a03cad19501f017587cc4e47d8418273834b Patch Third Party Advisory
https://github.com/netblue30/firejail/releases/tag/0.9.64.4 Release Notes Third Party Advisory
https://lists.debian.org/debian-lts-announce/2021/02/msg00015.html Third Party Advisory
https://security.gentoo.org/glsa/202105-19 Third Party Advisory
https://unparalleled.eu/blog/2021/20210208-rigged-race-against-firejail-for-local-root/ Exploit Third Party Advisory
https://unparalleled.eu/publications/2021/advisory-unpar-2021-0.txt Exploit Third Party Advisory
https://www.debian.org/security/2021/dsa-4849 Third Party Advisory
http://www.openwall.com/lists/oss-security/2021/02/09/1 Exploit Mailing List Patch Third Party Advisory
https://github.com/netblue30/firejail/commit/97d8a03cad19501f017587cc4e47d8418273834b Patch Third Party Advisory
https://github.com/netblue30/firejail/releases/tag/0.9.64.4 Release Notes Third Party Advisory
https://lists.debian.org/debian-lts-announce/2021/02/msg00015.html Third Party Advisory
https://security.gentoo.org/glsa/202105-19 Third Party Advisory
https://unparalleled.eu/blog/2021/20210208-rigged-race-against-firejail-for-local-root/ Exploit Third Party Advisory
https://unparalleled.eu/publications/2021/advisory-unpar-2021-0.txt Exploit Third Party Advisory
https://www.debian.org/security/2021/dsa-4849 Third Party Advisory
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2021-26910 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2021-26910 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Profile Photo
orgTestCodacy11KRepos110MB/repo-1121-firejail

None

Makefile Shell M4 Python Vim Script C Roff Awk Perl

Updated: 2 years, 8 months ago
0 stars 0 fork 0 watcher
Born at : Jan. 30, 2023, 9:05 p.m. This repo has been linked 1 different CVEs too.
Profile Photo
sailfishos-mirror/firejail

https://github.com/netblue30/firejail.git

Makefile M4 Python Shell C Perl Awk Vim Script Roff

Updated: 1 week, 3 days ago
1 stars 0 fork 0 watcher
Born at : Feb. 26, 2021, 6:12 p.m. This repo has been linked 1 different CVEs too.
Profile Photo
netblue30/firejail

Linux namespaces and seccomp-bpf sandbox

Shell C Perl Makefile M4 Python Awk Roff Vim Script

Updated: 4 days, 19 hours ago
6707 stars 610 fork 610 watcher
Born at : Aug. 8, 2015, 10:25 p.m. This repo has been linked 1 different CVEs too.

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2021-26910 vulnerability anywhere in the article.

Results are limited to the first 20 news articles due to potential performance issues.

The following table lists the changes that have been made to the CVE-2021-26910 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by af854a3a-2127-422b-91ae-364da2661108

    Nov. 21, 2024

    Action Type Old Value New Value
    Added Reference http://www.openwall.com/lists/oss-security/2021/02/09/1
    Added Reference https://github.com/netblue30/firejail/commit/97d8a03cad19501f017587cc4e47d8418273834b
    Added Reference https://github.com/netblue30/firejail/releases/tag/0.9.64.4
    Added Reference https://lists.debian.org/debian-lts-announce/2021/02/msg00015.html
    Added Reference https://security.gentoo.org/glsa/202105-19
    Added Reference https://unparalleled.eu/blog/2021/20210208-rigged-race-against-firejail-for-local-root/
    Added Reference https://unparalleled.eu/publications/2021/advisory-unpar-2021-0.txt
    Added Reference https://www.debian.org/security/2021/dsa-4849
  • CVE Modified by [email protected]

    May. 14, 2024

    Action Type Old Value New Value
  • Modified Analysis by [email protected]

    May. 23, 2022

    Action Type Old Value New Value
    Changed Reference Type https://security.gentoo.org/glsa/202105-19 No Types Assigned https://security.gentoo.org/glsa/202105-19 Third Party Advisory
  • CVE Modified by [email protected]

    May. 26, 2021

    Action Type Old Value New Value
    Added Reference https://security.gentoo.org/glsa/202105-19 [No Types Assigned]
  • Initial Analysis by [email protected]

    Feb. 16, 2021

    Action Type Old Value New Value
    Added CVSS V2 NIST (AV:L/AC:M/Au:N/C:C/I:C/A:C)
    Added CVSS V3.1 NIST AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
    Changed Reference Type http://www.openwall.com/lists/oss-security/2021/02/09/1 No Types Assigned http://www.openwall.com/lists/oss-security/2021/02/09/1 Exploit, Mailing List, Patch, Third Party Advisory
    Changed Reference Type https://github.com/netblue30/firejail/commit/97d8a03cad19501f017587cc4e47d8418273834b No Types Assigned https://github.com/netblue30/firejail/commit/97d8a03cad19501f017587cc4e47d8418273834b Patch, Third Party Advisory
    Changed Reference Type https://github.com/netblue30/firejail/releases/tag/0.9.64.4 No Types Assigned https://github.com/netblue30/firejail/releases/tag/0.9.64.4 Release Notes, Third Party Advisory
    Changed Reference Type https://lists.debian.org/debian-lts-announce/2021/02/msg00015.html No Types Assigned https://lists.debian.org/debian-lts-announce/2021/02/msg00015.html Third Party Advisory
    Changed Reference Type https://unparalleled.eu/blog/2021/20210208-rigged-race-against-firejail-for-local-root/ No Types Assigned https://unparalleled.eu/blog/2021/20210208-rigged-race-against-firejail-for-local-root/ Exploit, Third Party Advisory
    Changed Reference Type https://unparalleled.eu/publications/2021/advisory-unpar-2021-0.txt No Types Assigned https://unparalleled.eu/publications/2021/advisory-unpar-2021-0.txt Exploit, Third Party Advisory
    Changed Reference Type https://www.debian.org/security/2021/dsa-4849 No Types Assigned https://www.debian.org/security/2021/dsa-4849 Third Party Advisory
    Added CWE NIST CWE-367
    Added CPE Configuration OR *cpe:2.3:a:firejail_project:firejail:*:*:*:*:*:*:*:* versions up to (excluding) 0.9.64.4
    Added CPE Configuration OR *cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:* *cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*
  • CVE Modified by [email protected]

    Feb. 11, 2021

    Action Type Old Value New Value
    Added Reference https://lists.debian.org/debian-lts-announce/2021/02/msg00015.html [No Types Assigned]
  • CVE Modified by [email protected]

    Feb. 10, 2021

    Action Type Old Value New Value
    Added Reference https://www.debian.org/security/2021/dsa-4849 [No Types Assigned]
  • CVE Modified by [email protected]

    Feb. 09, 2021

    Action Type Old Value New Value
    Added Reference http://www.openwall.com/lists/oss-security/2021/02/09/1 [No Types Assigned]
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
Vulnerability Scoring Details
Base CVSS Score: 7.8
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality Impact
Integrity Impact
Availability Impact
Base CVSS Score: 6.9
Access Vector
Access Complexity
Authentication
Confidentiality Impact
Integrity Impact
Availability Impact
Exploit Prediction

EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days.

0.05 }} -0.00%

score

0.15744

percentile