overview
A severe security flaw, tracked as CVE-2023-5129, has been discovered in the libwebp image library – a critical component for rendering WebP format images. The vulnerability poses significant risks and has been given a CVSS score of 10.
The root cause of the issue lies in the flawed implementation of the Huffman coding algorithm within the libwebp library. CVE-2023-5129 allows attackers to execute arbitrary code via a heap buffer overflow, potentially leading to system crashes, unauthorized data access, and arbitrary code execution.
Initially misidentified as a Google Chrome vulnerability (CVE-2023-4863), it has now been accurately identified as a critical flaw in libwebp. Earlier, security researchers mistakenly identified it as part of a zero-click iMessage exploit chain called BLASTPASS that targeted fully patched iPhones with NSO Group's Pegasus spyware. Although unconfirmed, it appears that the BLASTPASS chain was made possible by the libwebp vulnerability.
Researchers initially misidentified the vulnerability because Google quietly submitted another disclosure for a critical code-execution vulnerability. Their earlier disclosure gave the wrong impression that it only impacted the Chrome browser, but the new submission clarified its broader impact on thousands of apps and software frameworks.
For those who are not aware, the libwebp library is widespread, found in numerous critical applications, including popular web browsers (e.g., Chrome, Firefox, Microsoft Edge, Opera), Linux distributions (Debian, Ubuntu, Alpine, Gentoo, SUSE), the Electron framework, and many other widely-used applications (e.g., Microsoft Teams, Slack, Discord, LibreOffice). Some have already implemented patches for the vulnerability while others have not.
CVE-2023-5129 impacts libwebp versions 0.5.0 to 1.3.1, with the issue being addressed in version 1.3.2. Due to the severity of the vulnerability, Avertium recommends that users update libwebp and related applications as soon as possible.
INDICATORS OF COMPROMISE (IoCs)
At this time, there are no known IoCs associated with CVE-2023-5129. Avertium remains vigilant in locating IoCs for our customers. Should any be located, Avertium will disclose them as soon as possible. For more information on how Avertium can help protect your organization, please reach out to your Avertium Service Delivery Manager or Account Executive.SUPPORTING DOCUMENTATION
Google quietly corrects previously submitted disclosure for critical webp 0-day | Ars Technica
Google assigns new maximum rated CVE to libwebp bug exploited in attacks (bleepingcomputer.com)
Tom Sellers: "Roughly 2 weeks ago Google pat…" - Infosec Exchange
Google Max Severity Score for lipwebp Zero-day Exploited in Wild (cybersecuritynews.com)