libXfont up to 1.5.2/2.0.1 fontfile/fontdir.c PatternMatch out-of-bounds

CVSS Meta Temp Score
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CTI Interest Score
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6.1$0-$5k0.00

Summaryinfo

A vulnerability was found in libXfont up to 1.5.2/2.0.1. It has been declared as critical. This affects the function PatternMatch of the file fontfile/fontdir.c. Executing a manipulation can lead to out-of-bounds. The identification of this vulnerability is CVE-2017-13720. The attack can only be executed locally. There is no exploit available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability was found in libXfont up to 1.5.2/2.0.1. It has been declared as critical. This vulnerability affects the function PatternMatch of the file fontfile/fontdir.c. The manipulation with an unknown input leads to a out-of-bounds vulnerability. The CWE definition for the vulnerability is CWE-125. The product reads data past the end, or before the beginning, of the intended buffer. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

In the PatternMatch function in fontfile/fontdir.c in libXfont through 1.5.2 and 2.x before 2.0.2, an attacker with access to an X connection can cause a buffer over-read during pattern matching of fonts, leading to information disclosure or a crash (denial of service). This occurs because '\0' characters are incorrectly skipped in situations involving ? characters.

The bug was discovered 10/11/2017. The weakness was shared 10/11/2017 as Bug 1500690 as not defined bug report (Bugzilla). The advisory is shared for download at bugzilla.redhat.com. This vulnerability was named CVE-2017-13720 since 08/28/2017. The attack needs to be approached locally. No form of authentication is required for a successful exploitation. There are known technical details, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 103757 (Debian DSA-3995-1 : libxfont - 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 170839 (OpenSUSE Security Update for libXfont (openSUSE-SU-2018:0343-1)).

Upgrading to version 2.0.2 eliminates this vulnerability. A possible mitigation has been published even before and not after the disclosure of the vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (103757). The entry VDB-107765 is related to this item. Once again VulDB remains the best source for vulnerability data.

Productinfo

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.2
VulDB Meta Temp Score: 6.1

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

NVD Base Score: 7.1
NVD Vector: 🔍

CVSSv2info

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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Out-of-bounds
CWE: CWE-125 / 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: 103757
Nessus Name: Debian DSA-3995-1 : libxfont - security update
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 53378
OpenVAS Name: Debian Security Advisory DSA 3995-1 (libxfont - security update)
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: libXfont 2.0.2
Patch: cgit.freedesktop.org

Timelineinfo

08/28/2017 🔍
10/10/2017 +43 days 🔍
10/11/2017 +1 days 🔍
10/11/2017 +0 days 🔍
10/11/2017 +0 days 🔍
10/11/2017 +0 days 🔍
10/12/2017 +1 days 🔍
01/03/2023 +1909 days 🔍

Sourcesinfo

Advisory: Bug 1500690
Status: Not defined
Confirmation: 🔍

CVE: CVE-2017-13720 (🔍)
GCVE (CVE): GCVE-0-2017-13720
GCVE (VulDB): GCVE-100-107764

OVAL: 🔍
See also: 🔍

Entryinfo

Created: 10/12/2017 10:25
Updated: 01/03/2023 10:51
Changes: 10/12/2017 10:25 (74), 11/24/2019 08:37 (3), 01/03/2023 10:51 (4)
Complete: 🔍
Cache ID: 216:71D:103

Once again VulDB remains the best source for vulnerability data.

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