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Microsoft published security advisories for two vulnerabilities affecting separate components: CVE-2026-5861, a use-after-free flaw in Chromium's V8 JavaScript engine, and CVE-2026-31789, a heap buffer overflow in hexadecimal conversion logic. The advisories were released through Microsoft's Security Update Guide and identify memory-safety issues that could expose affected software to instability or potential code-execution scenarios depending on how the vulnerable components are reached.
The disclosures highlight continued risk from low-level memory corruption bugs in widely used software components, particularly browser engine code and data-conversion routines. Microsoft did not provide detailed public synopses in the referenced advisories, but the vulnerability classifications indicate that organizations should prioritize patch review and deployment for products that incorporate the affected Chromium and Microsoft code paths.
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2 events from the most recent confirmed update back to the earliest known activity.
Microsoft added CVE-2026-31789 to its Security Update Guide, describing it as a heap buffer overflow in hexadecimal conversion.
Microsoft added CVE-2026-5861 to its Security Update Guide, identifying it as a Chromium V8 use-after-free vulnerability.
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Microsoft published Security Update Guide entries for two Chromium vulnerabilities affecting different browser components: `CVE-2026-9124`, which maps to Chromium `CVE-2026-9123` and describes a heap buffer overflow in **Chromecast**, and `CVE-2024-5274`, a **type confusion** flaw in the **V8** JavaScript engine. The advisories indicate Microsoft is tracking upstream Chromium security issues through its own update guidance for downstream products that rely on Chromium components. The listed flaws affect memory safety in high-risk areas of the Chromium codebase, with one issue tied to media casting functionality and the other to JavaScript execution. While the entries provide limited public detail, the combination of a heap buffer overflow and a V8 type confusion bug signals potential browser exploitation risk and reinforces the need for organizations to prioritize vendor updates for Microsoft and Chromium-based software as patches become available.
Jul 12, 2026
Microsoft published security advisories for several **Chromium** vulnerabilities spanning browser components including **WebXR**, **WebRTC**, **V8**, and web apps. The issues are tracked as `CVE-2026-8583` (**insufficient policy enforcement in WebXR**), `CVE-2023-7024` (**heap buffer overflow in WebRTC**), `CVE-2022-1096` (**type confusion in V8**), and `CVE-2021-4052` (**use-after-free in web apps**), indicating exposure across both rendering and scripting-related functionality in Chromium-based environments. The listed flaws cover multiple high-risk bug classes commonly associated with browser compromise, including memory corruption and policy enforcement weaknesses. Microsoft surfaced the vulnerabilities through its Security Update Guide and portal advisories, signaling that organizations using Microsoft products that incorporate Chromium components should review applicable updates and assess browser-related attack surface tied to immersive web features, real-time communications, JavaScript execution, and web application handling.
Jul 12, 2026
Microsoft added **CVE-2026-9120** to its Security Update Guide as a **Chromium** flaw caused by a **use-after-free in WebRTC**, extending a pattern of browser-component memory-safety issues that have repeatedly affected Microsoft products built on Chromium. Related Microsoft advisories previously tracked similar upstream Chromium bugs including **CVE-2022-2294** (**heap buffer overflow in WebRTC**), **CVE-2022-2008** (**out-of-bounds memory access in WebGL**), **CVE-2021-4066** (**integer underflow in ANGLE**), and **CVE-2025-5419** (**out-of-bounds read/write in V8**). The broader set of Microsoft Security Update Guide entries also shows the company continuing to catalog third-party and legacy-component vulnerabilities that can lead to severe impact, including **OpenSSL CVE-2022-3602** affecting X.509 certificate verification and older **Jet Database Engine remote code execution** flaws such as **CVE-2019-0577**, **CVE-2019-0579**, and **CVE-2020-0995**. Together, the advisories highlight Microsoft's ongoing publication of high-risk memory-corruption and code-execution issues across browser, cryptographic, and database components that defenders should track for patching and exposure assessment.
Jul 12, 2026