# CVE-2021-42762: libwebkit2gtk-4.0-37: BubblewrapLauncher.cpp in WebKitGTK and WPE WebKit before 2.34.1 allows a limited sandbox bypass that allows a sandbo...

CVE-2021-42762 is fixed in 7 products on 1 platform, first by gir1.2-javascriptcoregtk-4.0 2.34.1-1ubuntu1, released October 20, 2021. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2021-42762
- Priority: Routine
- CVSS: n/a (Medium)
- EPSS: 0.0054
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Oct 20, 2021

## Description

BubblewrapLauncher.cpp in WebKitGTK and WPE WebKit before 2.34.1 allows a limited sandbox bypass that allows a sandboxed process to trick host processes into thinking the sandboxed process is not confined by the sandbox, by abusing VFS syscalls that manipulate its filesystem namespace. The impact is limited to host services that create UNIX sockets that WebKit mounts inside its sandbox, and the sandboxed process remains otherwise confined. NOTE: this is similar to CVE-2021-41133.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | gir1.2-javascriptcoregtk-4.0 Ubuntu 20.04 LTS (focal) | 2.34.1-0ubuntu0.20.04.1 | [gir1.2-javascriptcoregtk-4.0 2.34.1-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-gir1.2-javascriptcoregtk-4.0-2.34.1-0ubuntu0.20.04.1.md) | Dec 24, 2021 |
| Linux | gir1.2-javascriptcoregtk-4.0 Ubuntu 22.04.1 LTS (jammy) | 2.34.1-1ubuntu1 | [gir1.2-javascriptcoregtk-4.0 2.34.1-1ubuntu1](https://patchblox.com/security/data/fix/linux/ubuntu-jammy-gir1.2-javascriptcoregtk-4.0-2.34.1-1ubuntu1.md) | Oct 20, 2021 |
| Linux | gir1.2-webkit2-4.0 Ubuntu 20.04 LTS (focal) | 2.34.1-0ubuntu0.20.04.1 | [gir1.2-webkit2-4.0 2.34.1-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-gir1.2-webkit2-4.0-2.34.1-0ubuntu0.20.04.1.md) | Dec 24, 2021 |
| Linux | gir1.2-webkit2-4.0 Ubuntu 22.04.1 LTS (jammy) | 2.34.1-1ubuntu1 | [gir1.2-webkit2-4.0 2.34.1-1ubuntu1](https://patchblox.com/security/data/fix/linux/ubuntu-jammy-gir1.2-webkit2-4.0-2.34.1-1ubuntu1.md) | Oct 20, 2021 |
| Linux | libjavascriptcoregtk-4.0-18 Ubuntu 20.04 LTS (focal) | 2.34.1-0ubuntu0.20.04.1 | [libjavascriptcoregtk-4.0-18 2.34.1-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-libjavascriptcoregtk-4.0-18-2.34.1-0ubuntu0.20.04.1.md) | Dec 24, 2021 |
| Linux | libjavascriptcoregtk-4.0-18 Ubuntu 22.04.1 LTS (jammy) | 2.34.1-1ubuntu1 | [libjavascriptcoregtk-4.0-18 2.34.1-1ubuntu1](https://patchblox.com/security/data/fix/linux/ubuntu-jammy-libjavascriptcoregtk-4.0-18-2.34.1-1ubuntu1.md) | Oct 20, 2021 |
| Linux | libjavascriptcoregtk-4.0-bin Ubuntu 20.04 LTS (focal) | 2.34.1-0ubuntu0.20.04.1 | [libjavascriptcoregtk-4.0-bin 2.34.1-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-libjavascriptcoregtk-4.0-bin-2.34.1-0ubuntu0.20.04.1.md) | Dec 24, 2021 |
| Linux | libjavascriptcoregtk-4.0-bin Ubuntu 22.04.1 LTS (jammy) | 2.34.1-1ubuntu1 | [libjavascriptcoregtk-4.0-bin 2.34.1-1ubuntu1](https://patchblox.com/security/data/fix/linux/ubuntu-jammy-libjavascriptcoregtk-4.0-bin-2.34.1-1ubuntu1.md) | Oct 20, 2021 |
| Linux | libwebkit2gtk-4.0-37 Ubuntu 20.04 LTS (focal) | 2.34.1-0ubuntu0.20.04.1 | [libwebkit2gtk-4.0-37 2.34.1-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-libwebkit2gtk-4.0-37-2.34.1-0ubuntu0.20.04.1.md) | Dec 24, 2021 |
| Linux | libwebkit2gtk-4.0-37 Ubuntu 22.04.1 LTS (jammy) | 2.34.1-1ubuntu1 | [libwebkit2gtk-4.0-37 2.34.1-1ubuntu1](https://patchblox.com/security/data/fix/linux/ubuntu-jammy-libwebkit2gtk-4.0-37-2.34.1-1ubuntu1.md) | Oct 20, 2021 |
| Linux | libwebkit2gtk-4.0-37-gtk2 Ubuntu 20.04 LTS (focal) | 2.34.1-0ubuntu0.20.04.1 | [libwebkit2gtk-4.0-37-gtk2 2.34.1-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-libwebkit2gtk-4.0-37-gtk2-2.34.1-0ubuntu0.20.04.1.md) | Dec 24, 2021 |
| Linux | webkit2gtk-driver Ubuntu 20.04 LTS (focal) | 2.34.1-0ubuntu0.20.04.1 | [webkit2gtk-driver 2.34.1-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-webkit2gtk-driver-2.34.1-0ubuntu0.20.04.1.md) | Dec 24, 2021 |
| Linux | webkit2gtk-driver Ubuntu 22.04.1 LTS (jammy) | 2.34.1-1ubuntu1 | [webkit2gtk-driver 2.34.1-1ubuntu1](https://patchblox.com/security/data/fix/linux/ubuntu-jammy-webkit2gtk-driver-2.34.1-1ubuntu1.md) | Oct 20, 2021 |

---

Data as of 2026-11-09T07:25:28Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

Free to use with attribution: show "Data: Patchblox Patch Radar" with a link to https://patchblox.com/security/patch-radar. Terms, including what needs a written agreement: https://patchblox.com/security/patch-radar/use-the-data

Product names, logos and trademarks shown on Patch Radar belong to their respective owners. They are used only to identify the software each security fix applies to and to help readers find their platform. Their use does not imply any affiliation with, or endorsement by, those owners, and Patchblox is not affiliated with any of them.