CVE-2020-26959: Use After Free
During browser shutdown, reference decrementing could have occured on a previously freed object, resulting in a use-after-free, memory corruption, and a potentially exploitable crash.
Other sources
During browser shutdown, reference decrementing could have occurred on a previously freed object, resulting in a use-after-free, memory corruption, and a potentially exploitable crash.
— Mozilla
Affected Software
Event History
Parent advisories
This vulnerability appears in the following advisories.
Peer vulnerabilities
Found alongside the following vulnerabilities.
Frequently Asked Questions
What is the severity of CVE-2020-26959?
The severity of CVE-2020-26959 is high with a severity value of 8.8.
Which software is affected by CVE-2020-26959?
Firefox < 83, Firefox ESR < 78.5, and Thunderbird < 78.5 are affected by CVE-2020-26959.
How can the use-after-free vulnerability be exploited?
The use-after-free vulnerability in CVE-2020-26959 can potentially be exploited to cause a memory corruption and crash.
How can I fix CVE-2020-26959?
To fix CVE-2020-26959, update Mozilla Firefox to version 83 or later, Firefox ESR to version 78.5 or later, or Thunderbird to version 78.5 or later.
Where can I find more information about CVE-2020-26959?
You can find more information about CVE-2020-26959 in the following references: [Reference 1](https://bugzilla.mozilla.org/show_bug.cgi?id=1669466), [Reference 2](https://www.mozilla.org/en-US/security/advisories/mfsa2020-51/), [Reference 3](https://www.mozilla.org/security/advisories/mfsa2020-50/).