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Mozilla Foundation Security Advisory 2023-50

Security Vulnerabilities fixed in Firefox ESR 115.5.0

Announced
November 21, 2023
Impact
high
Products
Firefox ESR
Fixed in
  • Firefox ESR 115.5

#CVE-2023-6204: Out-of-bound memory access in WebGL2 blitFramebuffer

Reporter
JSec of Hayyim Security
Impact
high
Description

On some systems—depending on the graphics settings and drivers—it was possible to force an out-of-bounds read and leak memory data into the images created on the canvas element.

References

#CVE-2023-6205: Use-after-free in MessagePort::Entangled

Reporter
Yangkang of 360 ATA Team
Impact
high
Description

It was possible to cause the use of a MessagePort after it had already been freed, which could potentially have led to an exploitable crash.

References

#CVE-2023-6206: Clickjacking permission prompts using the fullscreen transition

Reporter
Hafiizh
Impact
high
Description

The black fade animation when exiting fullscreen is roughly the length of the anti-clickjacking delay on permission prompts. It was possible to use this fact to surprise users by luring them to click where the permission grant button would be about to appear.

References

#CVE-2023-6207: Use-after-free in ReadableByteStreamQueueEntry::Buffer

Reporter
Yangkang of 360 ATA Team
Impact
high
Description

Ownership mismanagement led to a use-after-free in ReadableByteStreams

References

#CVE-2023-6208: Using Selection API would copy contents into X11 primary selection.

Reporter
turistu
Impact
moderate
Description

When using X11, text selected by the page using the Selection API was erroneously copied into the primary selection, a temporary storage not unlike the clipboard.
This bug only affects Firefox on X11. Other systems are unaffected.

References

#CVE-2023-6209: Incorrect parsing of relative URLs starting with "///"

Reporter
Rachmat Abdul Rokhim
Impact
moderate
Description

Relative URLs starting with three slashes were incorrectly parsed, and a path-traversal "/../" part in the path could be used to override the specified host. This could contribute to security problems in web sites.

References

#CVE-2023-6212: Memory safety bugs fixed in Firefox 120, Firefox ESR 115.5, and Thunderbird 115.5

Reporter
Mozilla Developers
Impact
high
Description

Memory safety bugs present in Firefox 119, Firefox ESR 115.4, and Thunderbird 115.4. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code.

References