CVE-2017-1000121

Severity: critical (CVSS 9.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2017-11-01 · updated 2026-06-17
Weakness: CWE-190

Description

The UNIX IPC layer in WebKit, including WebKitGTK+ prior to 2.16.3, does not properly validate message size metadata, allowing a compromised secondary process to trigger an integer overflow and subsequent buffer overflow in the UI process. This vulnerability does not affect Apple products.

Affected products

Webkitgtk+: before 2.16.3 — fixed in 2.16.3

How to fix

Upgrade to a fixed version: Webkitgtk+ 2.16.3. Check the vendor advisory for mitigations.

References

http://trac.webkit.org/changeset/217126/webkit
https://webkitgtk.org/security/WSA-2017-0007.html
http://trac.webkit.org/changeset/217126/webkit

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