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Vulnerability DatabaseCVE-2021-45931

CVE-2021-45931: 
NixOS vulnerability analysis and mitigation

Overview

HarfBuzz 2.9.0, an OpenType text shaping library, was found to contain an out-of-bounds write vulnerability in the hbbitsetinvertiblet::set function, which is called from hbsparsesett::set and hbsetcopy (NVD, OSS-Fuzz). The vulnerability was discovered in August 2021 and was assigned CVE-2021-45931.

Technical details

The vulnerability is classified as an out-of-bounds write (CWE-787) with a CVSS v3.1 base score of 6.5 (Medium). The attack vector is network-based, with low attack complexity and requires user interaction. The vulnerability affects the boundary checking in the hbbitsetinvertiblet::set function (NVD).

Impact

If exploited, this vulnerability could lead to high availability impact on the affected system, though there are no direct impacts on confidentiality or integrity. The CVSS scoring indicates that while the vulnerability is exploitable remotely, it requires user interaction to be successful (NVD).

Mitigation and workarounds

The vulnerability was fixed in HarfBuzz version 2.9.1. Various Linux distributions have released security updates to address this issue, including Fedora and Gentoo. Users are advised to upgrade to HarfBuzz version 2.9.1 or later (Gentoo, Fedora).

Additional resources

Source: This report was generated using AI

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