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Multiple critical vulnerabilities were identified in Mozilla Firefox and Firefox ESR, with the most severe enabling arbitrary code execution. Affected versions include Firefox prior to 146, Firefox ESR prior to 115.31, and Firefox ESR prior to 140.6. The vulnerabilities include use-after-free in WebRTC (CVE-2025-14321), sandbox escape in Graphics (CVE-2025-14322), privilege escalation in the DOM (CVE-2025-14323), JIT miscompilation in the JavaScript Engine (CVE-2025-14324, CVE-2025-14325), and multiple memory safety bugs. Exploitation could allow attackers to install programs, modify or delete data, or create new accounts with full user rights, depending on the privileges of the compromised user. There are currently no reports of these vulnerabilities being exploited in the wild.
Security advisories from both the Canadian Centre for Cyber Security and the Multi-State Information Sharing and Analysis Center (MS-ISAC) urge users and administrators to apply the latest updates immediately to mitigate risk. The advisories highlight the importance of prompt patching, especially for large organizations and government entities, as the risk is assessed as high for these sectors. The updates address all known vulnerabilities, and users with fewer system privileges are less impacted than those with administrative rights.
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3 events from the most recent confirmed update back to the earliest known activity.
Rocky Linux issued product errata RLSA-2026:5932 covering Mozilla security updates, reflecting downstream distribution of fixes for affected Mozilla software in Rocky Linux. This represents vendor-specific availability of patched packages after Mozilla's original advisories.
Mozilla released updates for affected Mozilla products, with reporting noting Firefox, Firefox ESR, and Thunderbird versions as impacted. The advisories recommended immediate patching and stated that no exploitation in the wild had been reported at the time.
Mozilla published security advisories addressing multiple vulnerabilities in Firefox and Firefox ESR, including issues that could lead to arbitrary code execution. The affected versions were Firefox prior to 146, Firefox ESR prior to 115.31, and Firefox ESR prior to 140.6.
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Mozilla released Firefox ESR 140.6 to address several high and moderate impact security vulnerabilities, including use-after-free, sandbox escape, privilege escalation, JIT miscompilation, and same-origin policy bypass issues. Notable vulnerabilities include `CVE-2025-14321` (use-after-free in WebRTC: Signaling), `CVE-2025-14322` (sandbox escape in Graphics: CanvasWebGL), and multiple privilege escalation flaws in the DOM: Notifications and Netmonitor components. Several JIT miscompilation bugs in the JavaScript Engine were also patched, which could potentially allow attackers to execute arbitrary code. Additionally, memory safety bugs affecting previous versions of Firefox ESR, Thunderbird, and Firefox were resolved, with some showing evidence of memory corruption that could be exploited. Mozilla recommends updating to Firefox ESR 140.6 to mitigate these risks and ensure systems are protected against these vulnerabilities.
Jun 29, 2026
Mozilla released Firefox 146, addressing a series of high-impact security vulnerabilities, including several use-after-free flaws, privilege escalation issues, and a sandbox escape. Notable vulnerabilities include `CVE-2025-14321` (use-after-free in WebRTC: Signaling), `CVE-2025-14322` (sandbox escape in Graphics: CanvasWebGL), and multiple privilege escalation bugs in components such as DOM: Notifications and Netmonitor. Several JIT miscompilation vulnerabilities in the JavaScript Engine were also patched, along with a same-origin policy bypass and spoofing issue in the Downloads Panel. The update also resolves memory safety bugs affecting both Firefox and Thunderbird, some of which could potentially be exploited for remote code execution. Mozilla rates the overall impact of these vulnerabilities as high, urging users to update to Firefox 146 promptly to mitigate risk. The advisories provide CVE identifiers and reference associated bug reports for further technical details.
Jun 29, 2026
Google and Mozilla released security updates for **Chrome**, **Firefox**, and **Firefox ESR** to fix multiple high-severity and critical browser vulnerabilities. Reporting on the latest releases says Chrome addressed **27 flaws**, including critical use-after-free bugs **`CVE-2026-15112`** in Ozone and **`CVE-2026-15129`** in the Views UI framework, both of which could allow arbitrary code execution through a crafted webpage. Separate Chrome advisories and follow-on reporting also highlighted another recent batch of fixes covering **18 security holes**, underscoring a sustained stream of browser patching activity. Mozilla's updates fixed two critical vulnerabilities, **`CVE-2026-49825`** and **`CVE-2026-49826`**, affecting the JavaScript engine and browser engine in Firefox and Firefox ESR. One report said **public exploit code is available** for both flaws, increasing the urgency for defenders to deploy updates quickly. Across the referenced advisories, the common risk is browser compromise through memory-corruption and related bugs that can lead to **credential theft, session hijacking, malware delivery, and broader enterprise access** if users remain on unpatched versions.
Jul 17, 2026