WebKitGTK and WPE WebKit Security Advisory WSA-2021-0006

• Date Reported: October 26, 2021

• Advisory ID: WSA-2021-0006

• CVE identifiers: CVE-2021-30846, CVE-2021-30848, CVE-2021-30849, CVE-2021-30851, CVE-2021-30858, CVE-2021-42762.

Several vulnerabilities were discovered in WebKitGTK and WPE WebKit.

• CVE-2021-30846

  • Versions affected: WebKitGTK and WPE WebKit before 2.34.0.
  • Credit to Sergei Glazunov of Google Project Zero.
  • Impact: Processing maliciously crafted web content may lead to arbitrary code execution. Description: A memory corruption issue was addressed with improved memory handling.

• CVE-2021-30848

  • Versions affected: WebKitGTK and WPE WebKit before 2.32.4.
  • Credit to Sergei Glazunov of Google Project Zero.
  • Impact: Processing maliciously crafted web content may lead to code execution. Description: A memory corruption issue was addressed with improved memory handling.

• CVE-2021-30849

  • Versions affected: WebKitGTK and WPE WebKit before 2.32.4.
  • Credit to Sergei Glazunov of Google Project Zero.
  • Impact: Processing maliciously crafted web content may lead to arbitrary code execution. Description: Multiple memory corruption issues were addressed with improved memory handling.

• CVE-2021-30851

  • Versions affected: WebKitGTK and WPE WebKit before 2.34.0.
  • Credit to Samuel Groß of Google Project Zero.
  • Impact: Processing maliciously crafted web content may lead to code execution. Description: A memory corruption vulnerability was addressed with improved locking.

• CVE-2021-30858

  • Versions affected: WebKitGTK and WPE WebKit before 2.32.4.
  • Credit to an anonymous researcher.
  • Impact: Processing maliciously crafted web content may lead to arbitrary code execution. Apple is aware of a report that this issue may have been actively exploited. Description: A use after free issue was addressed with improved memory management.

• CVE-2021-42762

  • Versions affected: WebKitGTK and WPE WebKit before 2.34.1.
  • Credit to an anonymous reporter.
  • BubblewrapLauncher.cpp 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.

We recommend updating to the latest stable versions of WebKitGTK and WPE WebKit. It is the best way to ensure that you are running safe versions of WebKit. Please check our websites for information about the latest stable releases.

Further information about WebKitGTK and WPE WebKit security advisories can be found at: https://webkitgtk.org/security.html or https://wpewebkit.org/security/.