Webkitgtk: use-after-free of jscvalue function parameters
Priority MEDIUM 40CWE-416Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- Required
- Attack complexity
- Low
- Impact type
- Code execution
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- Partial Red Hat: 13 fixed, 1 without a fix
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-416 and the CVSS impact.
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.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00469 40th percentileScored 2026-11-07
Fix Partial Red Hat: 9 advisoriesRed Hat: 13 fixed, 1 without a fix
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Total
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| WebKit | WebKit | 2.21.1 and later | — | No fix listed | CNA |
| WebKitGTK | WebKitGTK | 2.21.1 and later | — | No fix listed | CNA |
| Red Hat | Red Hat Enterprise Linux 7 Extended Lifecycle Support | — | 2.54.0-1.el7_9 | Patch available | CNA |
| Red Hat | Red Hat Enterprise Linux 8 | — | 2.54.0-1.el8_10 | Patch available | CNA |
| Red Hat | Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support | — | 2.54.0-1.el8_6 | Patch available | CNA |
| Red Hat | Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On | — | 2.54.0-1.el8_6 | Patch available | CNA |
| Red Hat | Red Hat Enterprise Linux 8.8 Telecommunications Update Service | — | 2.54.0-1.el8_8 | Patch available | CNA |
| Red Hat | Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions | — | 2.54.0-1.el8_8 | Patch available | CNA |
| Red Hat | Red Hat Enterprise Linux 9 | — | 2.54.0-1.el9_8 | Patch available | CNA |
| Red Hat | Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions | — | 2.54.0-1.el9_2 | Patch available | CNA |
| Red Hat | Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions | — | 2.54.0-1.el9_4 | Patch available | CNA |
| Red Hat | Red Hat Enterprise Linux 9.6 Extended Update Support | — | 2.54.0-1.el9_6 | Patch available | CNA |
| Red Hat | Red Hat Enterprise Linux 6 | — | — | No fix listed | CNA |
| Red Hat | Red Hat Enterprise Linux 7 | — | — | Not affected | CNA |
- WebKit VendorWebKit Affected 2.21.1 and later Fixed in — No fix listed CNA
- WebKitGTK VendorWebKitGTK Affected 2.21.1 and later Fixed in — No fix listed CNA
- Red Hat Enterprise Linux 7 Extended Lifecycle Support VendorRed Hat Affected — Fixed in 2.54.0-1.el7_9 Patch available CNA
- Red Hat Enterprise Linux 8 VendorRed Hat Affected — Fixed in 2.54.0-1.el8_10 Patch available CNA
- Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support VendorRed Hat Affected — Fixed in 2.54.0-1.el8_6 Patch available CNA
- Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On VendorRed Hat Affected — Fixed in 2.54.0-1.el8_6 Patch available CNA
- Red Hat Enterprise Linux 8.8 Telecommunications Update Service VendorRed Hat Affected — Fixed in 2.54.0-1.el8_8 Patch available CNA
- Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions VendorRed Hat Affected — Fixed in 2.54.0-1.el8_8 Patch available CNA
- Red Hat Enterprise Linux 9 VendorRed Hat Affected — Fixed in 2.54.0-1.el9_8 Patch available CNA
- Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions VendorRed Hat Affected — Fixed in 2.54.0-1.el9_2 Patch available CNA
- Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions VendorRed Hat Affected — Fixed in 2.54.0-1.el9_4 Patch available CNA
- Red Hat Enterprise Linux 9.6 Extended Update Support VendorRed Hat Affected — Fixed in 2.54.0-1.el9_6 Patch available CNA
- Red Hat Enterprise Linux 6 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Red Hat Enterprise Linux 7 VendorRed Hat Affected — Fixed in — Not affected CNA
CPE names CNA · 11
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:/o:redhat:rhel_els:7 | 7 | — | Red Hat |
| cpe:/a:redhat:enterprise_linux:8::appstream | 8 | — | Red Hat |
| cpe:/a:redhat:rhel_aus:8.6::appstream | 8.6 | — | Red Hat |
| cpe:/a:redhat:rhel_eus_long_life:8.6::appstream | 8.6 | — | Red Hat |
| cpe:/a:redhat:rhel_e4s:8.8::appstream | 8.8 | — | Red Hat |
| cpe:/a:redhat:rhel_tus:8.8::appstream | 8.8 | — | Red Hat |
| cpe:/a:redhat:enterprise_linux:9::appstream | 9 | — | Red Hat |
| cpe:/a:redhat:rhel_e4s:9.2::appstream | 9.2 | — | Red Hat |
| cpe:/a:redhat:rhel_e4s:9.4::appstream | 9.4 | — | Red Hat |
| cpe:/a:redhat:rhel_eus:9.6::appstream | 9.6 | — | Red Hat |
- cpe:/o:redhat:rhel_els:7 Versions 7 — ·Red Hat
- cpe:/a:redhat:enterprise_linux:8::appstream Versions 8 — ·Red Hat
- cpe:/a:redhat:rhel_aus:8.6::appstream Versions 8.6 — ·Red Hat
- cpe:/a:redhat:rhel_eus_long_life:8.6::appstream Versions 8.6 — ·Red Hat
- cpe:/a:redhat:rhel_e4s:8.8::appstream Versions 8.8 — ·Red Hat
- cpe:/a:redhat:rhel_tus:8.8::appstream Versions 8.8 — ·Red Hat
- cpe:/a:redhat:enterprise_linux:9::appstream Versions 9 — ·Red Hat
- cpe:/a:redhat:rhel_e4s:9.2::appstream Versions 9.2 — ·Red Hat
- cpe:/a:redhat:rhel_e4s:9.4::appstream Versions 9.4 — ·Red Hat
- cpe:/a:redhat:rhel_eus:9.6::appstream Versions 9.6 — ·Red Hat
Remediation
Red Hat 9 advisories
- RHSA-2026:95403 Released 2026-11-05 · Red Hat rating Criticalwebkit2gtk3 security update
- Red Hat Enterprise Linux AppStream AUS (v.8.4) webkit2gtk3-2.54.0-1.el8_4, webkit2gtk3-devel-2.54.0-1.el8_4, webkit2gtk3-jsc-2.54.0-1.el8_4 +1
- Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4) webkit2gtk3-2.54.0-1.el8_4, webkit2gtk3-devel-2.54.0-1.el8_4, webkit2gtk3-jsc-2.54.0-1.el8_4 +1
- RHSA-2026:93435 Released 2026-11-02 · Red Hat rating Criticalwebkit2gtk3 security update
- Red Hat Enterprise Linux AppStream E4S (v.8.8) webkit2gtk3-2.54.0-1.el8_8, webkit2gtk3-devel-2.54.0-1.el8_8, webkit2gtk3-jsc-2.54.0-1.el8_8 +1
- Red Hat Enterprise Linux AppStream TUS (v.8.8) webkit2gtk3-2.54.0-1.el8_8, webkit2gtk3-devel-2.54.0-1.el8_8, webkit2gtk3-jsc-2.54.0-1.el8_8 +1
- RHSA-2026:92339 Released 2026-10-29 · Red Hat rating Criticalwebkit2gtk3 security update
- Red Hat Enterprise Linux AppStream AUS (v.8.6) webkit2gtk3-2.54.0-1.el8_6, webkit2gtk3-devel-2.54.0-1.el8_6, webkit2gtk3-jsc-2.54.0-1.el8_6 +1
- Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6) webkit2gtk3-2.54.0-1.el8_6, webkit2gtk3-devel-2.54.0-1.el8_6, webkit2gtk3-jsc-2.54.0-1.el8_6 +1
Show 6 more Red Hat advisories
- RHSA-2026:92216 Released 2026-10-29 · Red Hat rating Criticalwebkit2gtk3 security update
- Red Hat Enterprise Linux AppStream E4S (v.9.4) webkit2gtk3-2.54.0-1.el9_4, webkit2gtk3-devel-2.54.0-1.el9_4, webkit2gtk3-jsc-2.54.0-1.el9_4 +1
- RHSA-2026:91631 Released 2026-10-28 · Red Hat rating Criticalwebkitgtk4 security update
- Red Hat Enterprise Linux Server (v. 7 ELS) webkitgtk4-2.54.0-1.el7_9, webkitgtk4-devel-2.54.0-1.el7_9, webkitgtk4-jsc-2.54.0-1.el7_9 +1
- Red Hat Enterprise Linux Server Optional (v. 7 ELS) webkitgtk4-devel-2.54.0-1.el7_9, webkitgtk4-doc-2.54.0-1.el7_9, webkitgtk4-jsc-devel-2.54.0-1.el7_9
- RHSA-2026:89822 Released 2026-10-27 · Red Hat rating Criticalwebkit2gtk3 security update
- Red Hat Enterprise Linux AppStream E4S (v.9.2) webkit2gtk3-2.54.0-1.el9_2, webkit2gtk3-devel-2.54.0-1.el9_2, webkit2gtk3-jsc-2.54.0-1.el9_2 +1
- RHSA-2026:89821 Released 2026-10-26 · Red Hat rating Criticalwebkit2gtk3 security update
- Red Hat Enterprise Linux AppStream EUS (v.9.6) webkit2gtk3-2.54.0-1.el9_6, webkit2gtk3-devel-2.54.0-1.el9_6, webkit2gtk3-jsc-2.54.0-1.el9_6 +1
- RHSA-2026:74084 Released 2026-09-30 · Red Hat rating Criticalwebkit2gtk3 security update
- Red Hat Enterprise Linux AppStream (v. 8) webkit2gtk3-2.54.0-1.el8_10, webkit2gtk3-devel-2.54.0-1.el8_10, webkit2gtk3-jsc-2.54.0-1.el8_10 +1
- RHSA-2026:69098 Released 2026-09-21 · Red Hat rating Importantwebkit2gtk3 security update
- Red Hat Enterprise Linux AppStream (v. 9) webkit2gtk3-2.54.0-1.el9_8, webkit2gtk3-devel-2.54.0-1.el9_8, webkit2gtk3-jsc-2.54.0-1.el9_8 +1
Vendor assessments
Red Hat
Red Hat rating: Important. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 6 | Affected | No fix planned: Out of support scope |
| Red Hat Enterprise Linux AppStream (v. 8) | Fixed | RHSA-2026:74084 |
| Red Hat Enterprise Linux AppStream (v. 9) | Fixed | RHSA-2026:69098 |
| Red Hat Enterprise Linux AppStream AUS (v.8.4) | Fixed | RHSA-2026:95403 |
| Red Hat Enterprise Linux AppStream AUS (v.8.6) | Fixed | RHSA-2026:92339 |
| Red Hat Enterprise Linux AppStream E4S (v.8.8) | Fixed | RHSA-2026:93435 |
| Red Hat Enterprise Linux AppStream E4S (v.9.2) | Fixed | RHSA-2026:89822 |
| Red Hat Enterprise Linux AppStream E4S (v.9.4) | Fixed | RHSA-2026:92216 |
| Red Hat Enterprise Linux AppStream EUS (v.9.6) | Fixed | RHSA-2026:89821 |
| Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4) | Fixed | RHSA-2026:95403 |
| Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6) | Fixed | RHSA-2026:92339 |
| Red Hat Enterprise Linux AppStream TUS (v.8.8) | Fixed | RHSA-2026:93435 |
| Red Hat Enterprise Linux Server (v. 7 ELS) | Fixed | RHSA-2026:91631 |
| Red Hat Enterprise Linux Server Optional (v. 7 ELS) | Fixed | RHSA-2026:91631 |
Not affected: 1 product
- Red Hat Enterprise Linux 7
Timeline
- 2026-10-02 Threatist record created from CVE-2026-78376
- 2026-10-03 Alias added: GHSA-qcc7-6r53-qpph
- 2026-10-26 Fix available: webkit2gtk3@0:2.54.0-1.el9_6 · CNA
- 2026-10-26 1 new reference · CNA
- 2026-10-26 Fix available: RHSA-2026:89821 · Red Hat
- 2026-10-26 Fix available: Red Hat Enterprise Linux AppStream EUS (v.9.6) · Red Hat
- 2026-10-27 Fix available: webkit2gtk3@0:2.54.0-1.el9_2 · CNA
- 2026-10-27 1 new reference · CNA
- 2026-10-27 Fix available: Red Hat Enterprise Linux AppStream E4S (v.9.2) · Red Hat
- 2026-10-28 Fix available: webkitgtk4@0:2.54.0-1.el7_9 · CNA
- 2026-10-28 1 new reference · CNA
- 2026-10-29 Fix available: Red Hat Enterprise Linux Server (v. 7 ELS), Red Hat Enterprise Linux Server Optional (v. 7 ELS) · Red Hat
- 2026-10-29 Fix available: RHSA-2026:89822 · Red Hat
- 2026-10-29 Fix available: RHSA-2026:91631 · Red Hat
- 2026-10-29 Fix available: webkit2gtk3@0:2.54.0-1.el8_6, webkit2gtk3@0:2.54.0-1.el9_4 · CNA
- 2026-10-29 2 new references · CNA
- 2026-10-30 Fix available: RHSA-2026:92216 · Red Hat
- 2026-10-30 Fix available: RHSA-2026:92339 · Red Hat
- 2026-10-30 Fix available: Red Hat Enterprise Linux AppStream AUS (v.8.6), Red Hat Enterprise Linux AppStream E4S (v.9.4), Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6) · Red Hat
- 2026-11-02 Fix available: webkit2gtk3@0:2.54.0-1.el8_8 · CNA
- 2026-11-02 1 new reference · CNA
- 2026-11-02 Fix available: RHSA-2026:93435 · Red Hat
- 2026-11-02 Fix available: Red Hat Enterprise Linux AppStream E4S (v.8.8), Red Hat Enterprise Linux AppStream TUS (v.8.8) · Red Hat
- 2026-11-05 Fix available: Red Hat Enterprise Linux AppStream AUS (v.8.4), Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4) · Red Hat
- 2026-11-06 Fix available: RHSA-2026:95403 · Red Hat
References
More WebKit vulnerabilities
- TI-2020-08024 Use after free in Apple Safari CVSS 3.1HIGH 8.8
- TI-2018-08811 WebCore/platform/graphics/texmap/TextureMapperLayer.cpp in WebKit, as used in WebKitGTK+… CVSS 3.0HIGH 8.8
- TI-2018-03164 In iOS before 11.3, Safari before 11.1, iCloud for Windows before 7.4, tvOS before 11.3… CVSS 3.0HIGH 8.8
- TI-2026-57696 Webkitgtk: validate the full featurelist array once in opentypeverticaldata findfeature CVSS 3.1HIGH 8.8
- TI-2023-20826 Use after free in Webkit CVSS 3.1HIGH 8.8
- TI-2020-08021 Type confusion in Apple Safari CVSS 3.1HIGH 8.8
Sources
- CVE-2026-78376 · CVE Program
- CVE-2026-78376 · NVD
- FIRST EPSS
- GHSA-qcc7-6r53-qpph · GitHub Advisory Database · CC BY 4.0
- CVE-2026-78376 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences