9.8
CRITICAL
CVE-2021-31535
X.Org X X11 RCE (Color Name Injection)
Description

LookupCol.c in X.Org X through X11R7.7 and libX11 before 1.7.1 might allow remote attackers to execute arbitrary code. The libX11 XLookupColor request (intended for server-side color lookup) contains a flaw allowing a client to send color-name requests with a name longer than the maximum size allowed by the protocol (and also longer than the maximum packet size for normal-sized packets). The user-controlled data exceeding the maximum size is then interpreted by the server as additional X protocol requests and executed, e.g., to disable X server authorization completely. For example, if the victim encounters malicious terminal control sequences for color codes, then the attacker may be able to take full control of the running graphical session.

INFO

Published Date :

May 27, 2021, 1:15 p.m.

Last Modified :

Nov. 21, 2024, 6:05 a.m.

Source :

[email protected]

Remotely Exploitable :

Yes !

Impact Score :

5.9

Exploitability Score :

3.9
Public PoC/Exploit Available at Github

CVE-2021-31535 has a 10 public PoC/Exploit available at Github. Go to the Public Exploits tab to see the list.

Affected Products

The following products are affected by CVE-2021-31535 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 X.org libx11
2 X.org x_window_system
1 Fedoraproject fedora
: Total Affected Vendor : 2 | Products : 3
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-2021-31535.

URL Resource
http://packetstormsecurity.com/files/162737/libX11-Insufficient-Length-Check-Injection.html Exploit Third Party Advisory VDB Entry
http://seclists.org/fulldisclosure/2021/May/52 Mailing List Third Party Advisory
http://www.openwall.com/lists/oss-security/2021/05/18/2 Mailing List Third Party Advisory
https://gitlab.freedesktop.org/xorg/lib/libx11/-/commit/8d2e02ae650f00c4a53deb625211a0527126c605 Third Party Advisory
https://lists.apache.org/thread.html/r61db8e7dcb56dc000a5387a88f7a473bacec5ee01b9ff3f55308aacc%40%3Cdev.kafka.apache.org%3E
https://lists.apache.org/thread.html/r61db8e7dcb56dc000a5387a88f7a473bacec5ee01b9ff3f55308aacc%40%3Cusers.kafka.apache.org%3E
https://lists.apache.org/thread.html/rbf4ce74b0d1fa9810dec50ba3ace0caeea677af7c27a97111c06ccb7%40%3Cdev.kafka.apache.org%3E
https://lists.apache.org/thread.html/rbf4ce74b0d1fa9810dec50ba3ace0caeea677af7c27a97111c06ccb7%40%3Cusers.kafka.apache.org%3E
https://lists.debian.org/debian-lts-announce/2021/05/msg00021.html Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TEOT4RLB76RVPJQKGGTIKTBIOLHX2NR6/
https://lists.freedesktop.org/archives/xorg/ Third Party Advisory
https://lists.x.org/archives/xorg-announce/2021-May/003088.html Vendor Advisory
https://security.gentoo.org/glsa/202105-16 Third Party Advisory
https://security.netapp.com/advisory/ntap-20210813-0001/ Third Party Advisory
https://unparalleled.eu/blog/2021/20210518-using-xterm-to-navigate-the-huge-color-space/ Exploit Third Party Advisory
https://unparalleled.eu/publications/2021/advisory-unpar-2021-1.txt Exploit Third Party Advisory
https://www.debian.org/security/2021/dsa-4920 Third Party Advisory
https://www.openwall.com/lists/oss-security/2021/05/18/2 Mailing List Third Party Advisory
https://www.openwall.com/lists/oss-security/2021/05/18/3 Mailing List Third Party Advisory
http://packetstormsecurity.com/files/162737/libX11-Insufficient-Length-Check-Injection.html Exploit Third Party Advisory VDB Entry
http://seclists.org/fulldisclosure/2021/May/52 Mailing List Third Party Advisory
http://www.openwall.com/lists/oss-security/2021/05/18/2 Mailing List Third Party Advisory
https://gitlab.freedesktop.org/xorg/lib/libx11/-/commit/8d2e02ae650f00c4a53deb625211a0527126c605 Third Party Advisory
https://lists.apache.org/thread.html/r61db8e7dcb56dc000a5387a88f7a473bacec5ee01b9ff3f55308aacc%40%3Cdev.kafka.apache.org%3E
https://lists.apache.org/thread.html/r61db8e7dcb56dc000a5387a88f7a473bacec5ee01b9ff3f55308aacc%40%3Cusers.kafka.apache.org%3E
https://lists.apache.org/thread.html/rbf4ce74b0d1fa9810dec50ba3ace0caeea677af7c27a97111c06ccb7%40%3Cdev.kafka.apache.org%3E
https://lists.apache.org/thread.html/rbf4ce74b0d1fa9810dec50ba3ace0caeea677af7c27a97111c06ccb7%40%3Cusers.kafka.apache.org%3E
https://lists.debian.org/debian-lts-announce/2021/05/msg00021.html Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TEOT4RLB76RVPJQKGGTIKTBIOLHX2NR6/
https://lists.freedesktop.org/archives/xorg/ Third Party Advisory
https://lists.x.org/archives/xorg-announce/2021-May/003088.html Vendor Advisory
https://security.gentoo.org/glsa/202105-16 Third Party Advisory
https://security.netapp.com/advisory/ntap-20210813-0001/ Third Party Advisory
https://unparalleled.eu/blog/2021/20210518-using-xterm-to-navigate-the-huge-color-space/ Exploit Third Party Advisory
https://unparalleled.eu/publications/2021/advisory-unpar-2021-1.txt Exploit Third Party Advisory
https://www.debian.org/security/2021/dsa-4920 Third Party Advisory
https://www.openwall.com/lists/oss-security/2021/05/18/2 Mailing List Third Party Advisory
https://www.openwall.com/lists/oss-security/2021/05/18/3 Mailing List Third Party Advisory

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
bionic-linux/android_external_libX11

None

Makefile Shell M4 C Perl

Updated: 1 week, 4 days ago
0 stars 0 fork 0 watcher
Born at : Dec. 11, 2024, 8:40 a.m. This repo has been linked 5 different CVEs too.
Profile Photo
Lingmo-Archive/libx11

Core X11 protocol client library

Makefile Shell M4 C Perl

Updated: 2 months, 3 weeks ago
0 stars 0 fork 0 watcher
Born at : April 13, 2024, 4:12 p.m. This repo has been linked 5 different CVEs too.
Profile Photo
AWSXXF/xorg_mirror_libx11

None

Makefile Shell M4 C Perl

Updated: 1 year, 1 month ago
0 stars 0 fork 0 watcher
Born at : Nov. 5, 2023, 5:32 p.m. This repo has been linked 5 different CVEs too.
Profile Photo
balabit-deps/balabit-os-9-libx11

None

Makefile Shell M4 C Perl

Updated: 2 years, 1 month ago
0 stars 0 fork 0 watcher
Born at : Nov. 15, 2022, 6:10 a.m. This repo has been linked 1 different CVEs too.
Profile Photo
deepin-community/libx11

None

Makefile Shell M4 C Perl

Updated: 2 years, 3 months ago
0 stars 1 fork 1 watcher
Born at : Aug. 15, 2022, 11:38 a.m. This repo has been linked 5 different CVEs too.
Profile Photo
ciwei100000/libx11-debian

Mirror of libx11 packaging

Makefile Shell M4 C Perl

Updated: 3 years, 4 months ago
0 stars 0 fork 0 watcher
Born at : Aug. 8, 2021, 10:49 a.m. This repo has been linked 1 different CVEs too.
Profile Photo
janisozaur/libx11

None

Makefile Shell M4 C Perl

Updated: 3 years, 6 months ago
0 stars 0 fork 0 watcher
Born at : June 7, 2021, 2:36 p.m. This repo has been linked 1 different CVEs too.
Profile Photo
n0-traces/cve_monitor

Automatic monitor github cve using Github Actions

Python

Updated: 1 month, 2 weeks ago
1 stars 57 fork 57 watcher
Born at : April 7, 2021, 11:16 a.m. This repo has been linked 1008 different CVEs too.
Profile Photo
pexip/os-libx11

Packaging for libx11

Shell C Perl Makefile M4

Updated: 2 years, 6 months ago
0 stars 0 fork 0 watcher
Born at : Jan. 10, 2014, 10:09 p.m. This repo has been linked 1 different CVEs too.
Profile Photo
mirror/libX11

Xlib/libX11 mirror

Shell C Perl Makefile M4

Updated: 3 weeks, 4 days ago
163 stars 62 fork 62 watcher
Born at : June 12, 2013, 7:46 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-2021-31535 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2021-31535 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://packetstormsecurity.com/files/162737/libX11-Insufficient-Length-Check-Injection.html
    Added Reference http://seclists.org/fulldisclosure/2021/May/52
    Added Reference http://www.openwall.com/lists/oss-security/2021/05/18/2
    Added Reference https://gitlab.freedesktop.org/xorg/lib/libx11/-/commit/8d2e02ae650f00c4a53deb625211a0527126c605
    Added Reference https://lists.apache.org/thread.html/r61db8e7dcb56dc000a5387a88f7a473bacec5ee01b9ff3f55308aacc%40%3Cdev.kafka.apache.org%3E
    Added Reference https://lists.apache.org/thread.html/r61db8e7dcb56dc000a5387a88f7a473bacec5ee01b9ff3f55308aacc%40%3Cusers.kafka.apache.org%3E
    Added Reference https://lists.apache.org/thread.html/rbf4ce74b0d1fa9810dec50ba3ace0caeea677af7c27a97111c06ccb7%40%3Cdev.kafka.apache.org%3E
    Added Reference https://lists.apache.org/thread.html/rbf4ce74b0d1fa9810dec50ba3ace0caeea677af7c27a97111c06ccb7%40%3Cusers.kafka.apache.org%3E
    Added Reference https://lists.debian.org/debian-lts-announce/2021/05/msg00021.html
    Added Reference https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TEOT4RLB76RVPJQKGGTIKTBIOLHX2NR6/
    Added Reference https://lists.freedesktop.org/archives/xorg/
    Added Reference https://lists.x.org/archives/xorg-announce/2021-May/003088.html
    Added Reference https://security.gentoo.org/glsa/202105-16
    Added Reference https://security.netapp.com/advisory/ntap-20210813-0001/
    Added Reference https://unparalleled.eu/blog/2021/20210518-using-xterm-to-navigate-the-huge-color-space/
    Added Reference https://unparalleled.eu/publications/2021/advisory-unpar-2021-1.txt
    Added Reference https://www.debian.org/security/2021/dsa-4920
    Added Reference https://www.openwall.com/lists/oss-security/2021/05/18/2
    Added Reference https://www.openwall.com/lists/oss-security/2021/05/18/3
  • CVE Modified by [email protected]

    May. 14, 2024

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

    Nov. 07, 2023

    Action Type Old Value New Value
    Added Reference MITRE https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TEOT4RLB76RVPJQKGGTIKTBIOLHX2NR6/ [No types assigned]
    Added Reference MITRE https://lists.apache.org/thread.html/r61db8e7dcb56dc000a5387a88f7a473bacec5ee01b9ff3f55308aacc%40%3Cdev.kafka.apache.org%3E [No types assigned]
    Added Reference MITRE https://lists.apache.org/thread.html/r61db8e7dcb56dc000a5387a88f7a473bacec5ee01b9ff3f55308aacc%40%3Cusers.kafka.apache.org%3E [No types assigned]
    Added Reference MITRE https://lists.apache.org/thread.html/rbf4ce74b0d1fa9810dec50ba3ace0caeea677af7c27a97111c06ccb7%40%3Cusers.kafka.apache.org%3E [No types assigned]
    Added Reference MITRE https://lists.apache.org/thread.html/rbf4ce74b0d1fa9810dec50ba3ace0caeea677af7c27a97111c06ccb7%40%3Cdev.kafka.apache.org%3E [No types assigned]
    Removed Reference MITRE https://lists.fedoraproject.org/archives/list/[email protected]/message/TEOT4RLB76RVPJQKGGTIKTBIOLHX2NR6/
    Removed Reference MITRE https://lists.apache.org/thread.html/r61db8e7dcb56dc000a5387a88f7a473bacec5ee01b9ff3f55308aacc@%3Cusers.kafka.apache.org%3E
    Removed Reference MITRE https://lists.apache.org/thread.html/r61db8e7dcb56dc000a5387a88f7a473bacec5ee01b9ff3f55308aacc@%3Cdev.kafka.apache.org%3E
    Removed Reference MITRE https://lists.apache.org/thread.html/rbf4ce74b0d1fa9810dec50ba3ace0caeea677af7c27a97111c06ccb7@%3Cusers.kafka.apache.org%3E
    Removed Reference MITRE https://lists.apache.org/thread.html/rbf4ce74b0d1fa9810dec50ba3ace0caeea677af7c27a97111c06ccb7@%3Cdev.kafka.apache.org%3E
  • Modified Analysis by [email protected]

    Sep. 23, 2021

    Action Type Old Value New Value
    Changed Reference Type https://lists.apache.org/thread.html/r61db8e7dcb56dc000a5387a88f7a473bacec5ee01b9ff3f55308aacc@%3Cdev.kafka.apache.org%3E No Types Assigned https://lists.apache.org/thread.html/r61db8e7dcb56dc000a5387a88f7a473bacec5ee01b9ff3f55308aacc@%3Cdev.kafka.apache.org%3E Mailing List, Third Party Advisory
    Changed Reference Type https://lists.apache.org/thread.html/r61db8e7dcb56dc000a5387a88f7a473bacec5ee01b9ff3f55308aacc@%3Cusers.kafka.apache.org%3E No Types Assigned https://lists.apache.org/thread.html/r61db8e7dcb56dc000a5387a88f7a473bacec5ee01b9ff3f55308aacc@%3Cusers.kafka.apache.org%3E Mailing List, Third Party Advisory
    Changed Reference Type https://lists.apache.org/thread.html/rbf4ce74b0d1fa9810dec50ba3ace0caeea677af7c27a97111c06ccb7@%3Cdev.kafka.apache.org%3E No Types Assigned https://lists.apache.org/thread.html/rbf4ce74b0d1fa9810dec50ba3ace0caeea677af7c27a97111c06ccb7@%3Cdev.kafka.apache.org%3E Mailing List, Third Party Advisory
    Changed Reference Type https://lists.apache.org/thread.html/rbf4ce74b0d1fa9810dec50ba3ace0caeea677af7c27a97111c06ccb7@%3Cusers.kafka.apache.org%3E No Types Assigned https://lists.apache.org/thread.html/rbf4ce74b0d1fa9810dec50ba3ace0caeea677af7c27a97111c06ccb7@%3Cusers.kafka.apache.org%3E Mailing List, Third Party Advisory
    Changed Reference Type https://lists.fedoraproject.org/archives/list/[email protected]/message/TEOT4RLB76RVPJQKGGTIKTBIOLHX2NR6/ No Types Assigned https://lists.fedoraproject.org/archives/list/[email protected]/message/TEOT4RLB76RVPJQKGGTIKTBIOLHX2NR6/ Mailing List, Third Party Advisory
    Changed Reference Type https://security.netapp.com/advisory/ntap-20210813-0001/ No Types Assigned https://security.netapp.com/advisory/ntap-20210813-0001/ Third Party Advisory
    Added CPE Configuration OR *cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*
  • CVE Modified by [email protected]

    Sep. 02, 2021

    Action Type Old Value New Value
    Added Reference https://lists.apache.org/thread.html/rbf4ce74b0d1fa9810dec50ba3ace0caeea677af7c27a97111c06ccb7@%3Cusers.kafka.apache.org%3E [No Types Assigned]
    Added Reference https://lists.apache.org/thread.html/rbf4ce74b0d1fa9810dec50ba3ace0caeea677af7c27a97111c06ccb7@%3Cdev.kafka.apache.org%3E [No Types Assigned]
  • CVE Modified by [email protected]

    Aug. 31, 2021

    Action Type Old Value New Value
    Added Reference https://lists.apache.org/thread.html/r61db8e7dcb56dc000a5387a88f7a473bacec5ee01b9ff3f55308aacc@%3Cusers.kafka.apache.org%3E [No Types Assigned]
    Added Reference https://lists.apache.org/thread.html/r61db8e7dcb56dc000a5387a88f7a473bacec5ee01b9ff3f55308aacc@%3Cdev.kafka.apache.org%3E [No Types Assigned]
  • CVE Modified by [email protected]

    Aug. 22, 2021

    Action Type Old Value New Value
    Added Reference https://lists.fedoraproject.org/archives/list/[email protected]/message/TEOT4RLB76RVPJQKGGTIKTBIOLHX2NR6/ [No Types Assigned]
  • CVE Modified by [email protected]

    Aug. 13, 2021

    Action Type Old Value New Value
    Added Reference https://security.netapp.com/advisory/ntap-20210813-0001/ [No Types Assigned]
  • Initial Analysis by [email protected]

    Jun. 10, 2021

    Action Type Old Value New Value
    Added CVSS V2 NIST (AV:N/AC:L/Au:N/C:P/I:P/A:P)
    Added CVSS V3.1 NIST AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
    Changed Reference Type http://packetstormsecurity.com/files/162737/libX11-Insufficient-Length-Check-Injection.html No Types Assigned http://packetstormsecurity.com/files/162737/libX11-Insufficient-Length-Check-Injection.html Exploit, Third Party Advisory, VDB Entry
    Changed Reference Type http://seclists.org/fulldisclosure/2021/May/52 No Types Assigned http://seclists.org/fulldisclosure/2021/May/52 Mailing List, Third Party Advisory
    Changed Reference Type http://www.openwall.com/lists/oss-security/2021/05/18/2 No Types Assigned http://www.openwall.com/lists/oss-security/2021/05/18/2 Mailing List, Third Party Advisory
    Changed Reference Type https://gitlab.freedesktop.org/xorg/lib/libx11/-/commit/8d2e02ae650f00c4a53deb625211a0527126c605 No Types Assigned https://gitlab.freedesktop.org/xorg/lib/libx11/-/commit/8d2e02ae650f00c4a53deb625211a0527126c605 Third Party Advisory
    Changed Reference Type https://lists.debian.org/debian-lts-announce/2021/05/msg00021.html No Types Assigned https://lists.debian.org/debian-lts-announce/2021/05/msg00021.html Third Party Advisory
    Changed Reference Type https://lists.freedesktop.org/archives/xorg/ No Types Assigned https://lists.freedesktop.org/archives/xorg/ Third Party Advisory
    Changed Reference Type https://lists.x.org/archives/xorg-announce/2021-May/003088.html No Types Assigned https://lists.x.org/archives/xorg-announce/2021-May/003088.html Vendor Advisory
    Changed Reference Type https://security.gentoo.org/glsa/202105-16 No Types Assigned https://security.gentoo.org/glsa/202105-16 Third Party Advisory
    Changed Reference Type https://unparalleled.eu/blog/2021/20210518-using-xterm-to-navigate-the-huge-color-space/ No Types Assigned https://unparalleled.eu/blog/2021/20210518-using-xterm-to-navigate-the-huge-color-space/ Exploit, Third Party Advisory
    Changed Reference Type https://unparalleled.eu/publications/2021/advisory-unpar-2021-1.txt No Types Assigned https://unparalleled.eu/publications/2021/advisory-unpar-2021-1.txt Exploit, Third Party Advisory
    Changed Reference Type https://www.debian.org/security/2021/dsa-4920 No Types Assigned https://www.debian.org/security/2021/dsa-4920 Third Party Advisory
    Changed Reference Type https://www.openwall.com/lists/oss-security/2021/05/18/2 No Types Assigned https://www.openwall.com/lists/oss-security/2021/05/18/2 Mailing List, Third Party Advisory
    Changed Reference Type https://www.openwall.com/lists/oss-security/2021/05/18/3 No Types Assigned https://www.openwall.com/lists/oss-security/2021/05/18/3 Mailing List, Third Party Advisory
    Added CWE NIST CWE-120
    Added CPE Configuration OR *cpe:2.3:a:x.org:libx11:*:*:*:*:*:*:*:* versions up to (excluding) 1.7.1 *cpe:2.3:o:x.org:x_window_system:*:*:*:*:*:*:*:* versions up to (including) x11r7.7
  • CVE Modified by [email protected]

    Jun. 07, 2021

    Action Type Old Value New Value
    Added Reference https://lists.x.org/archives/xorg-announce/2021-May/003088.html [No Types Assigned]
    Added Reference https://lists.debian.org/debian-lts-announce/2021/05/msg00021.html [No Types Assigned]
    Added Reference http://packetstormsecurity.com/files/162737/libX11-Insufficient-Length-Check-Injection.html [No Types Assigned]
    Added Reference https://www.debian.org/security/2021/dsa-4920 [No Types Assigned]
    Added Reference http://www.openwall.com/lists/oss-security/2021/05/18/2 [No Types Assigned]
    Added Reference https://security.gentoo.org/glsa/202105-16 [No Types Assigned]
    Added Reference http://seclists.org/fulldisclosure/2021/May/52 [No Types Assigned]
    Added Reference https://gitlab.freedesktop.org/xorg/lib/libx11/-/commit/8d2e02ae650f00c4a53deb625211a0527126c605 [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.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2021-31535 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-2021-31535 weaknesses.

CAPEC-8: Buffer Overflow in an API Call Buffer Overflow in an API Call CAPEC-9: Buffer Overflow in Local Command-Line Utilities Buffer Overflow in Local Command-Line Utilities CAPEC-10: Buffer Overflow via Environment Variables Buffer Overflow via Environment Variables CAPEC-14: Client-side Injection-induced Buffer Overflow Client-side Injection-induced Buffer Overflow CAPEC-24: Filter Failure through Buffer Overflow Filter Failure through Buffer Overflow CAPEC-42: MIME Conversion MIME Conversion CAPEC-44: Overflow Binary Resource File Overflow Binary Resource File CAPEC-45: Buffer Overflow via Symbolic Links Buffer Overflow via Symbolic Links CAPEC-46: Overflow Variables and Tags Overflow Variables and Tags CAPEC-47: Buffer Overflow via Parameter Expansion Buffer Overflow via Parameter Expansion CAPEC-67: String Format Overflow in syslog() String Format Overflow in syslog() CAPEC-92: Forced Integer Overflow Forced Integer Overflow CAPEC-100: Overflow Buffers Overflow Buffers
Exploit Prediction

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

23.96 }} 12.87%

score

0.96609

percentile

CVSS31 - Vulnerability Scoring System
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality
Integrity
Availability
: