Your submission was sent successfully! Close

You have successfully unsubscribed! Close

Thank you for signing up for our newsletter!
In these regular emails you will find the latest updates about Ubuntu and upcoming events where you can meet our team.Close

CVE-2021-31535

Published: 18 May 2021

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.

Priority

Medium

Cvss 3 Severity Score

9.8

Score breakdown

Status

Package Release Status
libx11
Launchpad, Ubuntu, Debian
impish
Released (1.7.0-2ubuntu1)
jammy
Released (1.7.0-2ubuntu1)
trusty
Released (2:1.6.2-1ubuntu2.1+esm2)
Available with Ubuntu Pro or Ubuntu Pro (Infra-only)
upstream Needs triage

xenial
Released (2:1.6.3-1ubuntu2.2+esm1)
Available with Ubuntu Pro or Ubuntu Pro (Infra-only)
bionic
Released (2:1.6.4-3ubuntu0.4)
focal
Released (2:1.6.9-2ubuntu1.2)
groovy
Released (2:1.6.12-1ubuntu0.1)
hirsute
Released (2:1.7.0-2ubuntu0.1)
Patches:
upstream: https://gitlab.freedesktop.org/xorg/lib/libx11/-/commit/8d2e02ae650f00c4a53deb625211a0527126c605

Severity score breakdown

Parameter Value
Base score 9.8
Attack vector Network
Attack complexity Low
Privileges required None
User interaction None
Scope Unchanged
Confidentiality High
Integrity impact High
Availability impact High
Vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H