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Mozilla Foundation Security Advisory 2021-11

Security Vulnerabilities fixed in Firefox ESR 78.9

Announced
March 23, 2021
Impact
high
Products
Firefox ESR
Fixed in
  • Firefox ESR 78.9

Note: This advisory was updated June 8, 2021 to include CVE-2021-29955 which was also fixed in this release.

#CVE-2021-29955: Transient Execution Vulnerability allowed leaking arbitrary memory address

Reporter
Hany Ragab, Enrico Barberis, Herbert Bos, and Cristiano Giuffrida from the VUSec group at VU Amsterdam
Impact
high
Description

A transient execution vulnerability, named Floating Point Value Injection (FPVI) allowed an attacker to leak arbitrary memory addresses and may have also enabled JIT type confusion attacks. (A related vulnerability, Speculative Code Store Bypass (SCSB), did not affect Firefox.)

References

#CVE-2021-23981: Texture upload into an unbound backing buffer resulted in an out-of-bound read

Reporter
Abraruddin Khan and Omair
Impact
high
Description

A texture upload of a Pixel Buffer Object could have confused the WebGL code to skip binding the buffer used to unpack it, resulting in memory corruption and a potentially exploitable information leak or crash.

References

#CVE-2021-4127: Angle graphics library out of date

Reporter
Mozilla Developers, Abraruddin Khan and Omair
Impact
high
Description

An out of date graphics library (Angle) likely contained vulnerabilities that could potentially be exploited.

References

#CVE-2021-23982: Internal network hosts could have been probed by a malicious webpage

Reporter
Samy Kamkar, Ben Seri, and Gregory Vishnepolsky
Impact
moderate
Description

Using techniques that built on the slipstream research, a malicious webpage could have scanned both an internal network's hosts as well as services running on the user's local machine utilizing WebRTC connections.

References

#CVE-2021-23984: Malicious extensions could have spoofed popup information

Reporter
Rob Wu
Impact
moderate
Description

A malicious extension could have opened a popup window lacking an address bar. The title of the popup lacking an address bar should not be fully controllable, but in this situation was. This could have been used to spoof a website and attempt to trick the user into providing credentials.

References

#CVE-2021-23987: Memory safety bugs fixed in Firefox 87 and Firefox ESR 78.9

Reporter
Mozilla developers and community
Impact
high
Description

Mozilla developers and community members Alexis Beingessner, Tyson Smith, Julien Wajsberg, and Matthew Gregan reported memory safety bugs present in Firefox 86 and Firefox ESR 78.8. 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