CVE-2026-78376
Webkitgtk: use-after-free of jscvalue function parameters
02 Description
Webkitgtk: use-after-free of jscvalue function parameters
03 Exploitation and scoring
- Exploitation
- Assessed, none found. CISA's assessment recorded neither public exploit code nor evidence of exploitation when it was made.
- SSVC decision
- ExploitationnoneCISA recorded no public exploit code and no evidence of exploitation.
- AutomatablenoAt least one step from reconnaissance to exploitation cannot be reliably automated.
- Technical ImpacttotalSuccessful exploitation gives total control of the vulnerable component.
- EPSS probability
- 0.38% probability of exploitation activity in the next 30 days.
- EPSS percentile
- Equal to or higher than the score of 32.8% of scored records. A rank, not a probability.
- NVD base score
- 8.8 (CVSS v3.x), scored by the NVD independently of the CNA.
- NVD CVSS vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
- NVD analysis status
- Awaiting Analysis. NVD last modified this record on 2026-10-28.
- Red Hat severity
- Important. Red Hat's rating for its own products, not a CVSS rating.
Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.
04 Metadata
- Published
- 2026-08-24 13:29Z2 MO AGO
- Last updated
- 2026-10-28 21:12Z20 HR AGO
- Reserved
- 2026-08-24
- Assigning CNA
- redhat
- Record state
- PUBLISHED
- Severity
- High (CVSS 8.8)
- CNA CVSS vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
- Weaknesses
- CWE-416Use After FreeVariant
- Data version
- 5.2
- Document digest
- 5a6ae4442471ef9b9a7d68c0d1a7f17c5f7ea8ea7c33e7af024390e21f6775e6
05 Affected products
06 References
- access.redhat.comRHSA-2026:69098https://access.redhat.com/errata/RHSA-2026:69098
- access.redhat.comRHSA-2026:74084https://access.redhat.com/errata/RHSA-2026:74084
- access.redhat.comRHSA-2026:89821https://access.redhat.com/errata/RHSA-2026:89821
- access.redhat.comRHSA-2026:89822https://access.redhat.com/errata/RHSA-2026:89822
- access.redhat.comRHSA-2026:91631https://access.redhat.com/errata/RHSA-2026:91631
- access.redhat.comhttps://access.redhat.com/security/cve/CVE-2026-78376
- bugzilla.redhat.comRHBZ#2521858https://bugzilla.redhat.com/show_bug.cgi?id=2521858
- github.comhttps://github.com/WebKit/WebKit/pull/72142
07 Fixed in
AlmaLinux 8
- webkit2gtk3 Fixed in 2.54.0-1.el8_10
- webkit2gtk3-devel Fixed in 2.54.0-1.el8_10
- webkit2gtk3-jsc Fixed in 2.54.0-1.el8_10
- webkit2gtk3-jsc-devel Fixed in 2.54.0-1.el8_10
Source: AlmaLinux, AlmaLinux OS. Copyright (c) 2023 AlmaLinux OS. Licensed under MIT License. Received through OSV.dev. Reformatted by exploit.cc.
AlmaLinux 9
- webkit2gtk3 Fixed in 2.54.0-1.el9_8
- webkit2gtk3-devel Fixed in 2.54.0-1.el9_8
- webkit2gtk3-jsc Fixed in 2.54.0-1.el9_8
- webkit2gtk3-jsc-devel Fixed in 2.54.0-1.el9_8
Source: AlmaLinux, AlmaLinux OS. Copyright (c) 2023 AlmaLinux OS. Licensed under MIT License. Received through OSV.dev. Reformatted by exploit.cc.
CloudLinux 8
- webkit2gtk3 Fixed in 2.54.0-1.el8_10
- webkit2gtk3-devel Fixed in 2.54.0-1.el8_10
- webkit2gtk3-jsc Fixed in 2.54.0-1.el8_10
- webkit2gtk3-jsc-devel Fixed in 2.54.0-1.el8_10
Derived from AlmaLinux 8. Partial coverage: only packages taken from AlmaLinux 8 are listed.
Source: CloudLinux errata, CloudLinux Inc. Derived from: AlmaLinux, AlmaLinux OS. Copyright (c) 2023 AlmaLinux OS. Licensed under MIT License. Received through OSV.dev. Reformatted by exploit.cc.
CloudLinux 9
- webkit2gtk3 Fixed in 2.54.0-1.el9_8
- webkit2gtk3-devel Fixed in 2.54.0-1.el9_8
- webkit2gtk3-jsc Fixed in 2.54.0-1.el9_8
- webkit2gtk3-jsc-devel Fixed in 2.54.0-1.el9_8
Derived from AlmaLinux 9. Partial coverage: only packages taken from AlmaLinux 9 are listed.
Source: CloudLinux errata, CloudLinux Inc. Derived from: AlmaLinux, AlmaLinux OS. Copyright (c) 2023 AlmaLinux OS. Licensed under MIT License. Received through OSV.dev. Reformatted by exploit.cc.
Debian 12
- webkit2gtk No fix yet
- wpewebkit No fix yet
Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.
Debian 13
- webkit2gtk Fixed in 2.54.0-1~deb13u1
- wpewebkit No fix yet
Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.
Debian 14
- webkit2gtk No fix yet
- wpewebkit Fixed in 2.54.0-1
Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu 16.04 LTS
- qtwebkit-opensource-src No fix yet
- qtwebkit-source No fix yet
- webkit2gtk No fix yet
- webkitgtk No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu 18.04 LTS
- qtwebkit-opensource-src No fix yet
- qtwebkit-source No fix yet
- webkit2gtk No fix yet
- webkitgtk No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu 20.04 LTS
- qtwebkit-opensource-src No fix yet
- webkit2gtk No fix yet
- wpewebkit No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu 22.04 LTS
- qtwebkit-opensource-src No fix yet
- webkit2gtk No fix yet
- wpewebkit No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu 24.04 LTS
- qtwebkit-opensource-src No fix yet
- webkit2gtk No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu 26.04 LTS
- webkit2gtk No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu 26.10
- webkit2gtk No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
A release or ecosystem missing from this list has no record here. It may be unaffected or not covered by the source. Source notices and licences.