CVE record · CVE-2026-78376

Webkitgtk: use-after-free of jscvalue function parameters

CVSS 8.8 HighEPSS 0.0047 · 40th percentile

Published by the CVE Program (CNA: redhat) at 24 Aug 2026, 13:29 UTC. agentprime has not analysed this yet, so whether it affects any app is not known. This CVE names a vendor and product rather than a package, so the lockfile check doesn’t match it.

Affected products, as the CNA wrote them
Vendor	Product	Versions
WebKit	WebKit Package name: webkit https://webkit.org/	affected 2.21.1 to before * semver Other versions: unaffected
WebKitGTK	WebKitGTK Package name: webkitgtk https://webkitgtk.org/	affected 2.21.1 to before * semver Other versions: unaffected
Red Hat	Red Hat Enterprise Linux 7 Extended Lifecycle Support Package name: webkitgtk4 https://access.redhat.com/downloads/content/package-browser/	unaffected 0:2.54.0-1.el7_9 to before * rpm Other versions: affected
Red Hat	Red Hat Enterprise Linux 8 Package name: webkit2gtk3 https://access.redhat.com/downloads/content/package-browser/	unaffected 0:2.54.0-1.el8_10 to before * rpm Other versions: affected
Red Hat	Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support Package name: webkit2gtk3 https://access.redhat.com/downloads/content/package-browser/	unaffected 0:2.54.0-1.el8_4 to before * rpm Other versions: affected
Red Hat	Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On Package name: webkit2gtk3 https://access.redhat.com/downloads/content/package-browser/	unaffected 0:2.54.0-1.el8_4 to before * rpm Other versions: affected
Red Hat	Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support Package name: webkit2gtk3 https://access.redhat.com/downloads/content/package-browser/	unaffected 0:2.54.0-1.el8_6 to before * rpm Other versions: affected
Red Hat	Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On Package name: webkit2gtk3 https://access.redhat.com/downloads/content/package-browser/	unaffected 0:2.54.0-1.el8_6 to before * rpm Other versions: affected
Red Hat	Red Hat Enterprise Linux 8.8 Telecommunications Update Service Package name: webkit2gtk3 https://access.redhat.com/downloads/content/package-browser/	unaffected 0:2.54.0-1.el8_8 to before * rpm Other versions: affected
Red Hat	Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions Package name: webkit2gtk3 https://access.redhat.com/downloads/content/package-browser/	unaffected 0:2.54.0-1.el8_8 to before * rpm Other versions: affected
Red Hat	Red Hat Enterprise Linux 9 Package name: webkit2gtk3 https://access.redhat.com/downloads/content/package-browser/	unaffected 0:2.54.0-1.el9_8 to before * rpm Other versions: affected
Red Hat	Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions Package name: webkit2gtk3 https://access.redhat.com/downloads/content/package-browser/	unaffected 0:2.54.0-1.el9_2 to before * rpm Other versions: affected
Red Hat	Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions Package name: webkit2gtk3 https://access.redhat.com/downloads/content/package-browser/	unaffected 0:2.54.0-1.el9_4 to before * rpm Other versions: affected
Red Hat	Red Hat Enterprise Linux 9.6 Extended Update Support Package name: webkit2gtk3 https://access.redhat.com/downloads/content/package-browser/	unaffected 0:2.54.0-1.el9_6 to before * rpm Other versions: affected
Red Hat	Red Hat Enterprise Linux 6 Package name: webkitgtk https://access.redhat.com/downloads/content/package-browser/	No versions given Other versions: unknown
Red Hat	Red Hat Enterprise Linux 7 Package name: webkitgtk3 https://access.redhat.com/downloads/content/package-browser/	No versions given Other versions: unaffected

Identifiers: CVE-2026-78376
CNA: redhat
Weakness (CWE): CWE-416
Tags: WebKit
WebKitGTK
Red Hat Enterprise Linux 7 Extended Lifecycle Support
Red Hat Enterprise Linux 8
Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support
Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On
Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support
Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On
Memory corruption
Published: 24 Aug 2026
Updated: 5 Nov 2026

Not analysed yet

We haven’t published our own analysis of this CVE. If a person reviews it, this page will say what’s affected and what has to be true for it to matter.

Severity and exploitation

Score	Rating	CVSS	Vector	Source
8.8	High	3.1	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H	CNA (redhat)

CISA KEV Not listed.
EPSS 0.0047, the 40th percentile, on 5 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

Timeline

24 Aug 2026, 13:29 UTC Confirmed by the CVE List
24 Aug 2026, 14:17 UTC Confirmed by NVD

Sources

References from the CNA

access.redhat.com/errata/RHSA-2026:69098 vendor-advisoryredhat
access.redhat.com/errata/RHSA-2026:74084 vendor-advisoryredhat
access.redhat.com/errata/RHSA-2026:89821 vendor-advisoryredhat
access.redhat.com/errata/RHSA-2026:89822 vendor-advisoryredhat
access.redhat.com/errata/RHSA-2026:91631 vendor-advisoryredhat
access.redhat.com/errata/RHSA-2026:92216 vendor-advisoryredhat
access.redhat.com/errata/RHSA-2026:92339 vendor-advisoryredhat
access.redhat.com/errata/RHSA-2026:93435 vendor-advisoryredhat
access.redhat.com/errata/RHSA-2026:95403 vendor-advisoryredhat
access.redhat.com/security/cve/CVE-2026-78376 vdb-entryredhat
bugzilla.redhat.com/show_bug.cgi?id=2521858 issue-trackingredhat
github.com/WebKit/WebKit/pull/72142

Facts on this page come from the CVE List as the CNA published them, with CVSS from the sources named above, CISA KEV and FIRST EPSS. Vendors, products and versions are shown as the CNA wrote them. We don’t reproduce the CVE’s description.