Is CVE-2026-92058 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-92058 being exploited in the wild.

How severe is CVE-2026-92058?

High severity, with a CVSS score of 8.8, published 15 September 2026.

Which products and versions are affected?

Mozilla Firefox before 156; Mozilla Firefox ESR before 153.3; Mozilla Thunderbird before 156; Mozilla Thunderbird ESR before 153.3.

Is there a fix for CVE-2026-92058?

A patch was published on 2026-09-15: Fixes released in Firefox 156, Firefox ESR 153.3, Thunderbird 156, and Thunderbird 153.3 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-92058 attacked?

It is attacked over the network.

Am I affected by CVE-2026-92058?

Check whether you run Mozilla Firefox, Mozilla Firefox ESR, Mozilla Thunderbird or one of the others listed at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-92058: Mozilla Firefox use-after-free in Graphics component

CVE-2026-92058 · Severity: high · CVSS 8.8 · Published 2026-09-15

Firefox is a widely-used web browser used by millions to access websites and online services. A use-after-free vulnerability in the Graphics component could allow an attacker to execute arbitrary code when a user visits a malicious website, potentially compromising the user's system and sensitive data. The vulnerability affects Firefox, Firefox ESR, Thunderbird, and Thunderbird ESR versions prior to the patched releases.

Technologies: Mozilla Firefox, Mozilla Firefox ESR, Mozilla Thunderbird, Mozilla Thunderbird ESR. Vendors: Mozilla.

Quick answers

Is CVE-2026-92058 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-92058 being exploited in the wild.
How severe is CVE-2026-92058?: High severity, with a CVSS score of 8.8, published 15 September 2026.
Which products and versions are affected?: Mozilla Firefox before 156; Mozilla Firefox ESR before 153.3; Mozilla Thunderbird before 156; Mozilla Thunderbird ESR before 153.3.
Is there a fix for CVE-2026-92058?: A patch was published on 2026-09-15: Fixes released in Firefox 156, Firefox ESR 153.3, Thunderbird 156, and Thunderbird 153.3 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-92058 attacked?: It is attacked over the network.
Am I affected by CVE-2026-92058?: Check whether you run Mozilla Firefox, Mozilla Firefox ESR, Mozilla Thunderbird or one of the others listed at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

CVE-2026-92058 is a use-after-free memory safety vulnerability in the Graphics component of Mozilla Firefox and Thunderbird. The vulnerability allows an attacker to trigger a crash or potentially achieve arbitrary code execution by exploiting improper memory management in the Graphics subsystem. The attack is network-based and requires user interaction (visiting a malicious website or opening a crafted file). Mozilla addressed this vulnerability in Firefox 156, Firefox ESR 153.3, Thunderbird 156, and Thunderbird 153.3.

Affected products

Mozilla Firefox before 156
Mozilla Firefox ESR before 153.3
Mozilla Thunderbird before 156
Mozilla Thunderbird ESR before 153.3

Timeline

2026-09-15: disclosed: CVE-2026-92058 publicly disclosed
2026-09-15: patched: Fixes released in Firefox 156, Firefox ESR 153.3, Thunderbird 156, and Thunderbird 153.3

References

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