Mozilla developers 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. This vulnerability affects Firefox < 81, Thunderbird < 78.3, and Firefox ESR < 78.3.
The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer.
| Link | Tags |
|---|---|
| https://www.mozilla.org/security/advisories/mfsa2020-43/ | release notes vendor advisory |
| https://www.mozilla.org/security/advisories/mfsa2020-44/ | release notes vendor advisory |
| https://www.mozilla.org/security/advisories/mfsa2020-42/ | release notes vendor advisory |
| https://bugzilla.mozilla.org/buglist.cgi?bug_id=1648493%2C1660800 | vendor advisory broken link issue tracking |
| https://www.debian.org/security/2020/dsa-4770 | third party advisory vendor advisory |
| https://lists.debian.org/debian-lts-announce/2020/10/msg00020.html | third party advisory mailing list |
| https://security.gentoo.org/glsa/202010-02 | third party advisory vendor advisory |
| http://lists.opensuse.org/opensuse-security-announce/2020-10/msg00074.html | vendor advisory mailing list third party advisory |
| http://lists.opensuse.org/opensuse-security-announce/2020-10/msg00077.html | vendor advisory mailing list third party advisory |