CVE-2021-34739
Published: 04 November 2021
Summary
CVE-2021-34739 is a high-severity Insufficient Session Expiration (CWE-613) vulnerability in Cisco Sf250-24 Firmware. Its CVSS base score is 8.1 (High).
Operationally, ranked in the top 33.4% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2021-21389
Vulnerability details
A vulnerability in the web-based management interface of multiple Cisco Small Business Series Switches could allow an unauthenticated, remote attacker to replay valid user session credentials and gain unauthorized access to the web-based management interface of an affected device. This…
more
vulnerability is due to insufficient expiration of session credentials. An attacker could exploit this vulnerability by conducting a man-in-the-middle attack against an affected device to intercept valid session credentials and then replaying the intercepted credentials toward the same device at a later time. A successful exploit could allow the attacker to access the web-based management interface with administrator privileges.
- 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.
Locks the device (typically after inactivity) until re-authentication, addressing insufficient session expiration by preventing indefinite access.
Automatically terminating sessions after a defined period directly enforces session expiration, preventing indefinite session lifetimes that attackers can exploit.
Re-authentication after inactivity or time-based triggers prevents indefinite use of potentially hijacked or stale sessions.
Terminating sessions and network connections upon completion prevents insufficient session expiration.
Directly enforces termination of network sessions after inactivity or end-of-session, preventing indefinite session lifetime.
Consistent clocks across systems allow session expiration and timeout enforcement to function as intended in distributed environments.
When the non-persistent artifact is a session or connection, mandatory termination implements the missing expiration that CWE-613 describes.
Timed refresh of session-related information or on-demand generation plus deletion implements proper session expiration.