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TI-2021-04821 Aliases CVE-2021-21775GHSA-ghh6-x87m-6qjh

Use after free in Webkit

Priority LOW 37CWE-416Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
Required
Attack complexity
Low
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
Partial Red Hat: 3 fixed, 2 without a fix

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-416 and the CVSS impact.

Summary

A use-after-free vulnerability exists in the way certain events are processed for ImageLoader objects of Webkit WebKitGTK 2.30.4. A specially crafted web page can lead to a potential information leak and further memory corruption. In order to trigger the vulnerability, a victim must be tricked into visiting a malicious webpage.

Why it matters now

EPSS 0.01274 70th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Partial Red Hat: 2 advisoriesRed Hat: 3 fixed, 2 without a fix

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
—WebkitWebkit WebKitGTK 2.30.4—No fix listedCNA
  • Webkit Vendor— Affected Webkit WebKitGTK 2.30.4 Fixed in — No fix listed CNA

CPE configurations NVD · 4

CPEVersionsRoleVendor
cpe:2.3:a:webkitgtk:webkitgtk:2.30.4:*:*:*:*:*:*:*2.30.4VulnerableWebKitGTK
cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*33VulnerableFedoraproject
cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*34VulnerableFedoraproject
cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*10.0VulnerableDebian
  • cpe:2.3:a:webkitgtk:webkitgtk:2.30.4:*:*:*:*:*:*:* Versions 2.30.4 Vulnerable ·WebKitGTK
  • cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:* Versions 33 Vulnerable ·Fedoraproject
  • cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:* Versions 34 Vulnerable ·Fedoraproject
  • cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:* Versions 10.0 Vulnerable ·Debian

Remediation

Red Hat 2 advisories

  • RHSA-2025:10364 Released 2025-07-07 · Red Hat rating Important
    webkitgtk4 security update
    • Red Hat Enterprise Linux Server (v. 7 ELS) webkitgtk4-2.48.3-2.el7_9, webkitgtk4-devel-2.48.3-2.el7_9, webkitgtk4-jsc-2.48.3-2.el7_9 +1
    • Red Hat Enterprise Linux Server Optional (v. 7 ELS) webkitgtk4-devel-2.48.3-2.el7_9, webkitgtk4-doc-2.48.3-2.el7_9, webkitgtk4-jsc-devel-2.48.3-2.el7_9
  • RHSA-2021:4381 Released 2021-11-09 · Red Hat rating Moderate
    GNOME security, bug fix, and enhancement update
    • Red Hat CodeReady Linux Builder (v. 8) LibRaw-devel-0.19.5-3.el8
    • Red Hat Enterprise Linux AppStream (v. 8) LibRaw-0.19.5-3.el8, gnome-autoar-0.2.3-2.el8, webkit2gtk3-2.32.3-2.el8 +3

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Advisory ·

    Webkit — FEDORA-2021-3de956ceee

    2 records Highest priority Priority MEDIUM 1 MEDIUM, 1 LOW

    Other records, highest priority first

    Show all 2 records → Advisory →
  • Advisory ·

    Webkit — FEDORA-2021-cf7d8c7b1a

    2 records Highest priority Priority MEDIUM 1 MEDIUM, 1 LOW

    Other records, highest priority first

    Show all 2 records → Advisory →
Show 1 more group

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux 6AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux 7AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux AppStream (v. 8)Fixed RHSA-2021:4381
Red Hat Enterprise Linux Server (v. 7 ELS)Fixed RHSA-2025:10364
Red Hat Enterprise Linux Server Optional (v. 7 ELS)Fixed RHSA-2025:10364
Not affected: 4 products
  • Red Hat CodeReady Linux Builder (v. 8)
  • Red Hat Enterprise Linux 9
  • Red Hat Enterprise Linux AppStream (v. 8)
  • Red Hat Enterprise Linux BaseOS (v. 8)

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-21775
  2. 2026-10-03 Alias added: GHSA-ghh6-x87m-6qjh

References

Exploit 1

Advisory 3

Other 1

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences