xkbcommon up to 0.8.0 Keymap File compose/parser.c resource management

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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4.3$0-$5k0.00

A vulnerability classified as problematic was found in xkbcommon up to 0.8.0. Affected by this vulnerability is an unknown code block of the file compose/parser.c of the component Keymap File Handler. The manipulation with an unknown input leads to a resource management vulnerability. The CWE definition for the vulnerability is CWE-399. As an impact it is known to affect availability. The summary by CVE is:

An infinite loop when reaching EOL unexpectedly in compose/parser.c (aka the keymap parser) in xkbcommon before 0.8.1 could be used by local attackers to cause a denial of service during parsing of crafted keymap files.

The bug was discovered 08/03/2018. The weakness was disclosed 08/25/2018 (Website). It is possible to read the advisory at github.com. This vulnerability is known as CVE-2018-15856 since 08/24/2018. The exploitation appears to be easy. Attacking locally is a requirement. The exploitation doesn't need any form of authentication. Technical details of the vulnerability are known, but there is no available exploit.

The vulnerability was handled as a non-public zero-day exploit for at least 22 days. During that time the estimated underground price was around $0-$5k. The vulnerability scanner Nessus provides a plugin with the ID 118505 (GLSA-201810-05 : xkbcommon: Multiple vulnerabilities), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Gentoo Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 197271 (Ubuntu Security Notification for Libxkbcommon Vulnerabilities (USN-3786-1)).

Upgrading to version 0.8.1 eliminates this vulnerability. A possible mitigation has been published 3 months after the disclosure of the vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (118505). The entries 123244, 123245, 123246 and 123248 are pretty similar.

Productinfo

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License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB CVSS-B Score: 🔍
VulDB CVSS-BT Score: 🔍
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.4
VulDB Meta Temp Score: 4.3

VulDB Base Score: 3.3
VulDB Temp Score: 3.2
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 5.5
NVD Vector: 🔍

CVSSv2info

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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
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NVD Base Score: 🔍

Exploitinginfo

Class: Resource management
CWE: CWE-399 / CWE-404
CAPEC: 🔍
ATT&CK: 🔍

Local: Yes
Remote: No

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 118505
Nessus Name: GLSA-201810-05 : xkbcommon: Multiple vulnerabilities
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

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

Upgrade: xkbcommon 0.8.1
Patch: github.com

Timelineinfo

08/03/2018 🔍
08/24/2018 +20 days 🔍
08/25/2018 +1 days 🔍
08/25/2018 +0 days 🔍
08/26/2018 +1 days 🔍
10/30/2018 +65 days 🔍
10/31/2018 +1 days 🔍
05/04/2023 +1646 days 🔍

Sourcesinfo

Advisory: RHSA-2019:2079
Status: Confirmed

CVE: CVE-2018-15856 (🔍)
See also: 🔍

Entryinfo

Created: 08/26/2018 08:58
Updated: 05/04/2023 14:53
Changes: 08/26/2018 08:58 (73), 03/18/2020 10:27 (2), 05/04/2023 14:53 (5)
Complete: 🔍

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