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                             CERT-Renater

                 Note d'Information No. 2020/VULN540
_____________________________________________________________________

DATE                : 25/09/2020

HARDWARE PLATFORM(S): /

OPERATING SYSTEM(S): Systems running Firefox versions prior to ESR 78.3,
                                            81.

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https://www.mozilla.org/en-US/security/advisories/mfsa2020-43/
https://www.mozilla.org/en-US/security/advisories/mfsa2020-42/
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Mozilla Foundation Security Advisory 2020-43
Security Vulnerabilities fixed in Firefox ESR 78.3

Announced        September 22, 2020
Impact           moderate
Products         Firefox ESR
Fixed in

        Firefox ESR 78.3

#CVE-2020-15677: Download origin spoofing via redirect

Reporter        Richard Thomas and Tom Chothia of University of
                 Birmingham
Impact          moderate

Description

By exploiting an Open Redirect vulnerability on a website, an attacker
could have spoofed the site displayed in the download file dialog to
show the original site (the one suffering from the open redirect) rather
than the site the file was actually downloaded from.

References

    Bug 1641487


#CVE-2020-15676: XSS when pasting attacker-controlled data into a
contenteditable element

Reporter        Daniel Fröjdendahl
Impact          moderate

Description

Firefox sometimes ran the onload handler for SVG elements that the DOM
sanitizer decided to remove, resulting in JavaScript being executed
after pasting attacker-controlled data into a contenteditable element.

References

    Bug 1646140


#CVE-2020-15678: When recursing through layers while scrolling, an
iterator may have become invalid, resulting in a potential use-after-
free scenario

Reporter        Lukas Bernhard
Impact          moderate

Description

When recursing through graphical layers while scrolling, an iterator may
have become invalid, resulting in a potential use-after-free. This
occurs because the function
APZCTreeManager::ComputeClippedCompositionBounds did not follow iterator
invalidation rules.

References

    Bug 1660211


#CVE-2020-15673: Memory safety bugs fixed in Firefox 81 and Firefox ESR 78.3

Reporter        Jason Kratzer
Impact          high

Description

Mozilla developer Jason Kratzer reported memory safety bugs present in
Firefox 80 and Firefox ESR 78.2. 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

    Memory safety bugs fixed in Firefox 81 and Firefox ESR 78.3

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Mozilla Foundation Security Advisory 2020-42
Security Vulnerabilities fixed in Firefox 81

Announced       September 22, 2020
Impact          high
Products        Firefox
Fixed in
        Firefox 81

#CVE-2020-15675: Use-After-Free in WebGL

Reporter        Brian Carpenter via the ASAN Nightly project
Impact          high

Description

When processing surfaces, the lifetime may outlive a persistent buffer
leading to memory corruption and a potentially exploitable crash.

References

    Bug 1654211


#CVE-2020-15677: Download origin spoofing via redirect

Reporter        Richard Thomas and Tom Chothia of University of
                 Birmingham
Impact          moderate

Description

By exploiting an Open Redirect vulnerability on a website, an attacker
could have spoofed the site displayed in the download file dialog to
show the original site (the one suffering from the open redirect) rather
than the site the file was actually downloaded from.

References

    Bug 1641487


#CVE-2020-15676: XSS when pasting attacker-controlled data into a
contenteditable element

Reporter        Daniel Fröjdendahl
Impact          moderate

Description

Firefox sometimes ran the onload handler for SVG elements that the DOM
sanitizer decided to remove, resulting in JavaScript being executed
after pasting attacker-controlled data into a contenteditable element.

References

    Bug 1646140


#CVE-2020-15678: When recursing through layers while scrolling, an
iterator may have become invalid, resulting in a potential use-after-
free scenario

Reporter        Lukas Bernhard
Impact          moderate

Description

When recursing through graphical layers while scrolling, an iterator may
have become invalid, resulting in a potential use-after-free. This
occurs because the function
APZCTreeManager::ComputeClippedCompositionBounds did not follow iterator
invalidation rules.

References

    Bug 1660211


#CVE-2020-15673: Memory safety bugs fixed in Firefox 81 and Firefox ESR 78.3

Reporter        Jason Kratzer
Impact           high

Description

Mozilla developer Jason Kratzer reported memory safety bugs present in
Firefox 80 and Firefox ESR 78.2. 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

    Memory safety bugs fixed in Firefox 81 and Firefox ESR 78.3


#CVE-2020-15674: Memory safety bugs fixed in Firefox 81

Reporter        Mozilla developers
Impact          high

Description

Mozilla developers Byron Campen and Christian Holler reported memory
safety bugs present in Firefox 80. 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

    Memory safety bugs fixed in Firefox 81



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