---
id: CVE-2026-78376
title: A flaw was found in WebKitGTK
summary: >-
  A flaw was found in WebKitGTK. Processing malicious web content can cause a
  use-after-free issue due to improper memory handling and result in memory
  corruption.
severity: high
cvss: 8.8
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H'
cwe:
  - CWE-416
vendor: WebKit
product: webkit
affected:
  - webkit >= 2.21.1 < *
  - webkitgtk >= 2.21.1 < *
  - webkit2gtk3 (all versions)
  - webkitgtk
  - webkitgtk3
  - webkitgtk4 (all versions)
  - webkit2gtk3 (all versions)
patched:
  - enterprise_linux_appstream_v_9
published: '2026-08-24'
updated: '2026-09-22'
sourceUpdated: '2026-09-22T15:17:15.333'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-78376'
references:
  - url: 'https://access.redhat.com/errata/RHSA-2026:69098'
    label: secalert@redhat.com
  - url: 'https://access.redhat.com/security/cve/CVE-2026-78376'
    label: secalert@redhat.com
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2521858'
    label: secalert@redhat.com
  - url: 'https://github.com/WebKit/WebKit/pull/72142'
    label: secalert@redhat.com
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-78376.json
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-78376'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-78376'
tags:
  - nvd
  - cve.org
  - csaf
  - vex
  - red-hat
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: total
  timestamp: '2026-08-24T00:00:00+00:00'
epss: 0.00285
epssPercentile: 0.1871
ingestedAt: '2026-09-21T16:49:07.870Z'
---

## Overview

A flaw was found in WebKitGTK. Processing malicious web content can cause a use-after-free issue due to improper memory handling and result in memory corruption.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

## Vendor advisories

- **RHSA-2026:69098** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 9) · released 2026-09-21 · [advisory](https://access.redhat.com/errata/RHSA-2026:69098)
- **Red Hat VEX** · Important · affected: Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8 · no fix planned: Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8 · updated 2026-09-22 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-78376.json)