Libksba up to 1.3.3 dn.c append_utf8_value numeric error

CVSS Meta Temp Score
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CTI Interest Score
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7.3$0-$5k0.00

A vulnerability classified as critical was found in Libksba up to 1.3.3. Affected by this vulnerability is the function append_utf8_value of the file dn.c. The manipulation with an unknown input leads to a numeric error vulnerability. The CWE definition for the vulnerability is CWE-189. As an impact it is known to affect availability. The summary by CVE is:

Off-by-one error in the append_utf8_value function in the DN decoder (dn.c) in Libksba before 1.3.4 allows remote attackers to cause a denial of service (out-of-bounds read) via invalid utf-8 encoded data. NOTE: this vulnerability exists because of an incomplete fix for CVE-2016-4356.

The weakness was presented 06/13/2016 (Website). The advisory is shared at ubuntu.com. This vulnerability is known as CVE-2016-4574 since 05/10/2016. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Technical details are known, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 91471 (Amazon Linux AMI : libksba (ALAS-2016-712)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Amazon Linux Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 196481 (Ubuntu Security Notification for Libksba Vulnerabilities (USN-2982-1)).

Upgrading to version 1.3.4 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 (91471). See 87907, 87908, 87909 and 87910 for similar entries.

Productinfo

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Version

CPE 2.3info

CPE 2.2info

CVSSv4info

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CVSSv3info

VulDB Meta Base Score: 7.5
VulDB Meta Temp Score: 7.3

VulDB Base Score: 7.5
VulDB Temp Score: 7.2
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VulDB Reliability: 🔍

NVD Base Score: 7.5
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CVSSv2info

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Exploitinginfo

Class: Numeric error
CWE: CWE-189
ATT&CK: Unknown

Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

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EPSS Percentile: 🔍

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Nessus ID: 91471
Nessus Name: Amazon Linux AMI : libksba (ALAS-2016-712)
Nessus File: 🔍
Nessus Risk: 🔍
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Nessus Context: 🔍

OpenVAS ID: 58353
OpenVAS Name: Ubuntu Update for libksba USN-2982-1
OpenVAS File: 🔍
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Qualys ID: 🔍
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Threat Intelligenceinfo

Interest: 🔍
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Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Libksba 1.3.4
Patch: 6be61daac047d8e6aa941eb103f8e71a1d4e3c75

Timelineinfo

05/10/2016 🔍
06/02/2016 +23 days 🔍
06/06/2016 +4 days 🔍
06/13/2016 +7 days 🔍
06/13/2016 +0 days 🔍
06/14/2016 +1 days 🔍
08/23/2022 +2261 days 🔍

Sourcesinfo

Advisory: USN-2982-1
Status: Not defined
Confirmation: 🔍

CVE: CVE-2016-4574 (🔍)
See also: 🔍

Entryinfo

Created: 06/14/2016 09:12
Updated: 08/23/2022 15:17
Changes: 06/14/2016 09:12 (62), 01/20/2019 13:22 (11), 08/23/2022 15:17 (6)
Complete: 🔍

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