CVE-2021-29962
Published: 24 June 2021
Summary
CVE-2021-29962 is a medium-severity Improper Resource Shutdown or Release (CWE-404) vulnerability in Mozilla Firefox. Its CVSS base score is 4.3 (Medium).
Operationally, ranked at the 48.0th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2021-16421
Vulnerability details
Firefox for Android would become unstable and hard-to-recover when a website opened too many popups. *This bug only affects Firefox for Android. Other operating systems are unaffected.*. This vulnerability affects Firefox < 89.
- CWE(s)
Related Threats
No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.
Affected Assets
Mitigating Controls
Likely Mitigating Controls AI
Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.
Contingency plan updates incorporate proper resource shutdown and release steps, preventing attackers from leveraging incomplete cleanup during recovery scenarios.
Mandates explicit shutdown of the network connection at session conclusion, directly addressing improper resource release.
Requires proper shutdown/release procedures that include overwriting or isolating data to block unintended transfer via reused system objects.
Procedures can mandate orderly shutdown or release of resources when failures occur, preventing improper resource handling after a fault.