CVE-2023-20042
Published: 01 November 2023
Summary
CVE-2023-20042 is a medium-severity Improper Resource Shutdown or Release (CWE-404) vulnerability in Cisco Adaptive Security Appliance Software. Its CVSS base score is 6.8 (Medium).
Operationally, ranked at the 48.9th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2023-24221
Vulnerability details
A vulnerability in the AnyConnect SSL VPN feature of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device.…
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This vulnerability is due to an implementation error within the SSL/TLS session handling process that can prevent the release of a session handler under specific conditions. An attacker could exploit this vulnerability by sending crafted SSL/TLS traffic to an affected device, increasing the probability of session handler leaks. A successful exploit could allow the attacker to eventually deplete the available session handler pool, preventing new sessions from being established and causing a DoS condition.
- 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.