Loading vulnerability…
CVE-2026-84125 is a use-after-free vulnerability in the DOM Core and HTML component of Mozilla Firefox and Thunderbird. The flaw can cause stale access to freed memory during DOM processing, resulting in memory corruption or application instability. It was fixed in Firefox 155, Firefox ESR 153.2, Thunderbird 155, and Thunderbird ESR 153.2.
Mallory correlates every CVE against your assets, your vendors, and active adversary campaigns. Know which vulnerabilities matter for you, not just which ones are loud.
What it means. What to do now. Patch path, mitigations, and the assume-compromise checklist.
What an attacker gets, and what they’ve been doing with it.
If you can’t patch tonight, do this now.
Patch, then assume compromise.
No public exploits tracked yet. Mallory keeps watching.
No public exploit code observed for this vulnerability.
Products and vendors Mallory has correlated with this vulnerability. Open in Mallory to drill down to specific CPE configurations and version ranges.
Vendor-confirmed product mapping. Mallory continuously reconciles this list against your asset inventory.
16 sources tracked across advisories, community write-ups, and news. New activity surfaces here as Mallory finds it.
A vulnerability addressed by the Fedora 44 Thunderbird update.
A use-after-free flaw in DOM Core and HTML.
A vulnerability addressed by the Fedora 45 Thunderbird security update; the vulnerability type is not specified.
An unspecified Firefox vulnerability fixed in Firefox ESR 153.2.0.
Query your assets running an affected version, and investigate the blast radius.
Every observed campaign linking this CVE to a named adversary.
Malware families riding this exploit, with evidence and IOCs.
YARA, Sigma, Snort, and vendor rules, auto-deployed to your SIEM.
Cross-references every affected SKU, including bundled OEM variants.
Community discussion across Reddit, Mastodon, and other social sources.