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Mozilla Foundation Security Advisory 2021-28

Security Vulnerabilities fixed in Firefox 90

Announced
July 13, 2021
Impact
high
Products
Firefox
Fixed in
  • Firefox 90

#CVE-2021-29970: Use-after-free in accessibility features of a document

Reporter
Irvan Kurniawan
Impact
high
Description

A malicious webpage could have triggered a use-after-free, memory corruption, and a potentially exploitable crash.
This bug only affected Firefox when accessibility was enabled.

References

#CVE-2021-29971: Granted permissions only compared host; omitting scheme and port on Android

Reporter
Arturo Mejia
Impact
high
Description

If a user had granted a permission to a webpage and saved that grant, any webpage running on the same host - irrespective of scheme or port - would be granted that permission.
This bug only affects Firefox for Android. Other operating systems are unaffected.

References

#CVE-2021-30547: Out of bounds write in ANGLE

Reporter
(Unknown)
Impact
high
Description

An out of bounds write in ANGLE could have allowed an attacker to corrupt memory leading to a potentially exploitable crash.

References

#CVE-2021-29972: Use of out-of-date library included use-after-free vulnerability

Reporter
Irvan Kurniawan
Impact
moderate
Description

A user-after-free vulnerability was found via testing, and traced to an out-of-date Cairo library. Updating the library resolved the issue, and may have remediated other, unknown security vulnerabilities as well.

References

#CVE-2021-29973: Password autofill on HTTP websites was enabled without user interaction on Android

Reporter
Wladimir Palant working with Include Security
Impact
moderate
Description

Password autofill was enabled without user interaction on insecure websites on Firefox for Android. This was corrected to require user interaction with the page before a user's password would be entered by the browser's autofill functionality.
This bug only affects Firefox for Android. Other operating systems are unaffected.

References

#CVE-2021-29974: HSTS errors could be overridden when network partitioning was enabled

Reporter
Peter Gerber
Impact
moderate
Description

When network partitioning was enabled, e.g. as a result of Enhanced Tracking Protection settings, a TLS error page would allow the user to override an error on a domain which had specified HTTP Strict Transport Security (which implies that the error should not be override-able.) This issue did not affect the network connections, and they were correctly upgraded to HTTPS automatically.

References

#CVE-2021-29975: Text message could be overlaid on top of another website

Reporter
Irvan Kurniawan
Impact
moderate
Description

Through a series of DOM manipulations, a message, over which the attacker had control of the text but not HTML or formatting, could be overlaid on top of another domain (with the new domain correctly shown in the address bar) resulting in possible user confusion.

References

#CVE-2021-29976: Memory safety bugs fixed in Firefox 90 and Firefox ESR 78.12

Reporter
Mozilla developers
Impact
high
Description

Mozilla developers Emil Ghitta, Tyson Smith, Valentin Gosu, Olli Pettay, and Randell Jesup reported memory safety bugs present in Firefox 89 and Firefox ESR 78.11. 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

#CVE-2021-29977: Memory safety bugs fixed in Firefox 90

Reporter
Mozilla developers
Impact
high
Description

Mozilla developers Andrew McCreight, Tyson Smith, Christian Holler, and Gabriele Svelto reported memory safety bugs present in Firefox 89. 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