X.Org Server up to 1.19.3 Global Buffer memory corruption

CVSS Meta Temp Score
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CTI Interest Score
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6.4$0-$5k0.00

Summaryinfo

A vulnerability marked as critical has been reported in X.Org Server up to 1.19.3. Affected is an unknown function of the component Global Buffer Handler. Performing a manipulation results in memory corruption. This vulnerability is identified as CVE-2017-13723. The attack is only possible with local access. There is not any exploit available. It is suggested to install a patch to address this issue.

Detailsinfo

A vulnerability was found in X.Org Server up to 1.19.3. It has been classified as critical. This affects an unknown code of the component Global Buffer Handler. The manipulation with an unknown input leads to a memory corruption vulnerability. CWE is classifying the issue as CWE-119. The product performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

In X.Org Server (aka xserver and xorg-server) before 1.19.4, a local attacker authenticated to the X server could overflow a global buffer, causing crashes of the X server or potentially other problems by injecting large or malformed XKB related atoms and accessing them via xkbcomp.

The bug was discovered 10/04/2017. The weakness was released 10/10/2017 (oss-sec). The advisory is shared at openwall.com. This vulnerability is uniquely identified as CVE-2017-13723 since 08/28/2017. An attack has to be approached locally. A authentication is needed for exploitation. Neither technical details nor an exploit are publicly available.

The vulnerability was handled as a non-public zero-day exploit for at least 5 days. During that time the estimated underground price was around $0-$5k. The vulnerability scanner Nessus provides a plugin with the ID 103882 (Debian DSA-4000-1 : xorg-server - security update), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Debian Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 196945 (Ubuntu Security Notification for Xorg-server, Xorg-server-hwe-16.04, Xorg-server-lts-xenial Vulnerabilities (USN-3453-1)).

Upgrading to version 1.19.4 eliminates this vulnerability. Applying a patch is able to eliminate this problem. The bugfix is ready for download at cgit.freedesktop.org. The best possible mitigation is suggested to be patching the affected component. A possible mitigation has been published 1 weeks after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at Tenable (103882) and SecurityFocus (BID 101253†). Entry connected to this vulnerability is available at VDB-107600. Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.5
VulDB Meta Temp Score: 6.4

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 7.8
NVD Vector: 🔍

CVSSv2info

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VulDB Base Score: 🔍
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Exploitinginfo

Class: Memory corruption
CWE: CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: No

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 103882
Nessus Name: Debian DSA-4000-1 : xorg-server - security update
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 53379
OpenVAS Name: Debian Security Advisory DSA 4000-1 (xorg-server - security update)
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

Interest: 🔍
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Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Patch
Status: 🔍

Reaction Time: 🔍
0-Day Time: 🔍
Exposure Time: 🔍

Upgrade: X.Org Server 1.19.4
Patch: cgit.freedesktop.org

Timelineinfo

08/28/2017 🔍
10/04/2017 +37 days 🔍
10/04/2017 +0 days 🔍
10/09/2017 +5 days 🔍
10/10/2017 +1 days 🔍
10/10/2017 +0 days 🔍
10/17/2017 +7 days 🔍
10/18/2017 +1 days 🔍
08/29/2025 +2872 days 🔍

Sourcesinfo

Advisory: DLA 1186-1
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2017-13723 (🔍)
GCVE (CVE): GCVE-0-2017-13723
GCVE (VulDB): GCVE-100-107601

OVAL: 🔍

SecurityFocus: 101253 - X.Org X Server 'xkbtext.c' Denial of Service Vulnerability

See also: 🔍

Entryinfo

Created: 10/10/2017 10:03
Updated: 08/29/2025 16:04
Changes: 10/10/2017 10:03 (79), 11/23/2019 08:13 (4), 01/03/2023 07:38 (4), 08/29/2025 16:04 (17)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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