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Mozilla Foundation Security Advisory 2020-20

Security Vulnerabilities fixed in Firefox 77

Announced
June 2, 2020
Impact
high
Products
Firefox
Fixed in
  • Firefox 77

#CVE-2020-12399: Timing attack on DSA signatures in NSS library

Reporter
Cesar Pereida Garcia and the Network and Information Security Group (NISEC) at Tampere University
Impact
high
Description

NSS has shown timing differences when performing DSA signatures, which was exploitable and could eventually leak private keys.

References

#CVE-2020-12405: Use-after-free in SharedWorkerService

Reporter
Marcin 'Icewall' Noga of Cisco Talos
Impact
high
Description

When browsing a malicious page, a race condition in our SharedWorkerService could occur and lead to a potentially exploitable crash.

References

#CVE-2020-12406: JavaScript type confusion with NativeTypes

Reporter
Iain Ireland
Impact
high
Description

Mozilla Developer Iain Ireland discovered a missing type check during unboxed objects removal, resulting in a crash. We presume that with enough effort that it could be exploited to run arbitrary code.

References

#CVE-2020-12407: WebRender leaking GPU memory when using border-image CSS directive

Reporter
Nicolas Silva
Impact
moderate
Description

Mozilla Developer Nicolas Silva found that when using WebRender, Firefox would under certain conditions leak arbitrary GPU memory to the visible screen. The leaked memory content was visible to the user, but not observable from web content.

References

#CVE-2020-12408: URL spoofing when using IP addresses

Reporter
Rayyan Bijoora
Impact
low
Description

When browsing a document hosted on an IP address, an attacker could insert certain characters to flip domain and path information in the address bar.

References

#CVE-2020-12409: URL spoofing with unicode characters

Reporter
Rayyan Bijoora
Impact
low
Description

When using certain blank characters in a URL, they where incorrectly rendered as spaces instead of an encoded URL.

References

#CVE-2020-12410: Memory safety bugs fixed in Firefox 77 and Firefox ESR 68.9

Reporter
Mozilla developers
Impact
high
Description

Mozilla developers Tom Tung and Karl Tomlinson reported memory safety bugs present in Firefox 76 and Firefox ESR 68.8. 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

#CVE-2020-12411: Memory safety bugs fixed in Firefox 77

Reporter
Mozilla developers
Impact
high
Description

Mozilla developers :Gijs (he/him), Randell Jesup reported memory safety bugs present in Firefox 76. 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