CVE-2026-78376
WebKitGTK use-after-free can lead to memory corruption and potential remote code execution.
Is CVE-2026-78376 being exploited?
Not confirmed. CVE-2026-78376 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.28% probability of exploitation in the next 30 days.
How severe is CVE-2026-78376?
CVE-2026-78376 is rated High with a CVSS score of 8.8. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-78376?
Not known from our data. No patch reference has been recorded for CVE-2026-78376, which is not the same as no patch existing — a fix may have shipped without a tagged reference, or after this record was written. The vendor advisory is the only authority on whether a fix exists, and mitigations may be available regardless.
What does CVE-2026-78376 affect?
CVE-2026-78376 affects WebKitGTK, GNOME Web (Epiphany), Linux browsers/apps using WebKitGTK, Embedded devices using WebKitGTK. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-78376?
Apply vendor patch when released; block or restrict untrusted WebKitGTK content.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Processing crafted web content can trigger a use-after-free memory corruption, enabling remote code execution or browser/process crash.
Immediate action required
- affected>= 2.21.1 and < *
- affected>= 2.21.1 and < *
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.