CVE-2020-15656

JIT optimizations involving the Javascript arguments object could confuse later optimizations. This risk was already mitigated by various precautions in the code, resulting in this bug rated at only moderate severity. This vulnerability affects Firefox ESR < 78.1, Firefox < 79, and Thunderbird < 78.1.

• CWE-843

• http://lists.opensuse.org/opensuse-security-announce/2020-08/msg00025.htmlThird Party Advisory
• https://bugzilla.mozilla.org/show_bug.cgi?id=1647293Issue Tracking, Permissions Required, Vendor Advisory
• https://usn.ubuntu.com/4443-1/Third Party Advisory
• https://www.mozilla.org/security/advisories/mfsa2020-30/Vendor Advisory
• https://www.mozilla.org/security/advisories/mfsa2020-32/Vendor Advisory
• https://www.mozilla.org/security/advisories/mfsa2020-33/Vendor Advisory
• http://lists.opensuse.org/opensuse-security-announce/2020-08/msg00025.htmlThird Party Advisory
• https://bugzilla.mozilla.org/show_bug.cgi?id=1647293Issue Tracking, Permissions Required, Vendor Advisory
• https://usn.ubuntu.com/4443-1/Third Party Advisory
• https://www.mozilla.org/security/advisories/mfsa2020-30/Vendor Advisory
• https://www.mozilla.org/security/advisories/mfsa2020-32/Vendor Advisory
• https://www.mozilla.org/security/advisories/mfsa2020-33/Vendor Advisory

Published

Aug 10, 2020

Last Modified

Jun 17, 2026

Status

Modified

• How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
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• CVE-2020-15650Given an installed malicious file picker application, an att…5.5
• CVE-2020-15651A unicode RTL order character in the downloaded file name ca…4.3
• CVE-2020-15652By observing the stack trace for JavaScript errors in web wo…6.5
• CVE-2020-15653An iframe sandbox element with the allow-popups flag could b…6.5
• CVE-2020-15654When in an endless loop, a website specifying a custom curso…6.5
• CVE-2020-15655A redirected HTTP request which is observed or modified thro…6.5
• CVE-2020-15657Firefox could be made to load attacker-supplied DLL files fr…7.8
• CVE-2020-15658The code for downloading files did not properly take care of…6.5
• CVE-2020-15659Mozilla developers and community members reported memory saf…8.8
• CVE-2020-1566An elevation of privilege vulnerability exists when the Wind…4.2
• CVE-2020-15660Missing checks on Content-Type headers in geckodriver before…8.8
• CVE-2020-15661A rogue webpage could override the injected WKUserScript use…6.5