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Mozilla Foundation Security Advisory 2021-15

Security Vulnerabilities fixed in Firefox ESR 78.10

Announced
April 19, 2021
Impact
high
Products
Firefox ESR
Fixed in
  • Firefox ESR 78.10

#CVE-2021-23994: Out of bound write due to lazy initialization

Reporter
Abraruddin Khan and Omair
Impact
high
Description

A WebGL framebuffer was not initialized early enough, resulting in memory corruption and an out of bound write.

References

#CVE-2021-23995: Use-after-free in Responsive Design Mode

Reporter
Irvan Kurniawan
Impact
high
Description

When Responsive Design Mode was enabled, it used references to objects that were previously freed. We presume that with enough effort this could have been exploited to run arbitrary code.

References

#CVE-2021-23998: Secure Lock icon could have been spoofed

Reporter
Jordi Chancel
Impact
moderate
Description

Through complicated navigations with new windows, an HTTP page could have inherited a secure lock icon from an HTTPS page.

References

#CVE-2021-23961: More internal network hosts could have been probed by a malicious webpage

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

Further techniques that built on the slipstream research combined with a malicious webpage could have exposed both an internal network's hosts as well as services running on the user's local machine.

References

#CVE-2021-23999: Blob URLs may have been granted additional privileges

Reporter
Nika Layzell
Impact
moderate
Description

If a Blob URL was loaded through some unusual user interaction, it could have been loaded by the System Principal and granted additional privileges that should not be granted to web content.

References

#CVE-2021-24002: Arbitrary FTP command execution on FTP servers using an encoded URL

Reporter
Daniel Santos
Impact
moderate
Description

When a user clicked on an FTP URL containing encoded newline characters (%0A and %0D), the newlines would have been interpreted as such and allowed arbitrary commands to be sent to the FTP server.

References

#CVE-2021-29945: Incorrect size computation in WebAssembly JIT could lead to null-reads

Reporter
Christian Holler
Impact
moderate
Description

The WebAssembly JIT could miscalculate the size of a return type, which could lead to a null read and result in a crash.
Note: This issue only affected x86-32 platforms. Other platforms are unaffected.

References

#CVE-2021-29946: Port blocking could be bypassed

Reporter
Frederik Braun
Impact
low
Description

Ports that were written as an integer overflow above the bounds of a 16-bit integer could have bypassed port blocking restrictions when used in the Alt-Svc header.

References