Cyber Resilience

CVE-2021-35473

Critical

Published: 10 November 2024

Published
10 November 2024
Modified
15 April 2026
KEV Added
Patch
CVSS Score v3.1 9.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
EPSS Score 0.0015 35.5th percentile
Risk Priority 18 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-35473 is a critical-severity Insufficient Session Expiration (CWE-613) vulnerability in Ow2 (inferred from references). Its CVSS base score is 9.1 (Critical).

Operationally, ranked at the 35.5th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability details

An issue was discovered in LemonLDAP::NG before 2.0.12. There is a missing expiration check in the OAuth2.0 handler, i.e., it does not verify access token validity. An attacker can use a expired access token from an OIDC client to access…

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the OAuth2 handler The earliest affected version is 2.0.4.

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

Ow2
inferred from references and description; NVD did not file a CPE for this CVE

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.

addresses: CWE-613

Locks the device (typically after inactivity) until re-authentication, addressing insufficient session expiration by preventing indefinite access.

addresses: CWE-613

Automatically terminating sessions after a defined period directly enforces session expiration, preventing indefinite session lifetimes that attackers can exploit.

addresses: CWE-613

Re-authentication after inactivity or time-based triggers prevents indefinite use of potentially hijacked or stale sessions.

addresses: CWE-613

Terminating sessions and network connections upon completion prevents insufficient session expiration.

addresses: CWE-613

Directly enforces termination of network sessions after inactivity or end-of-session, preventing indefinite session lifetime.

addresses: CWE-613

Consistent clocks across systems allow session expiration and timeout enforcement to function as intended in distributed environments.

addresses: CWE-613

When the non-persistent artifact is a session or connection, mandatory termination implements the missing expiration that CWE-613 describes.

addresses: CWE-613

Timed refresh of session-related information or on-demand generation plus deletion implements proper session expiration.

References