Cyber Resilience

CVE-2021-27899

High

Published: 06 April 2021

Published
06 April 2021
Modified
21 November 2024
KEV Added
Patch
CVSS Score v3.1 7.4 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
EPSS Score 0.0011 28.4th percentile
Risk Priority 15 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-27899 is a high-severity Improper Certificate Validation (CWE-295) vulnerability in Proofpoint Insider Threat Management. Its CVSS base score is 7.4 (High).

Operationally, ranked at the 28.4th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability details

The Proofpoint Insider Threat Management Agents (formerly ObserveIT Agent) for MacOS and Linux perform improper validation of the ITM Server's certificate, which enables a remote attacker to intercept and alter these communications using a man-in-the-middle attack. All versions before 7.11.1…

more

are affected. Agents for Windows and Cloud are not affected.

CWE(s)

Related Threats

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

Affected Assets

proofpoint
insider threat management
7.9.0 — 7.9.3 · 7.10.0 — 7.10.3 · 7.11.0 — 7.11.1

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-295

When certificates are used to establish component provenance, the control requires correct certificate validation procedures.

addresses: CWE-295

Mandates approved trust anchors and issuance policies, directly preventing acceptance of unvalidated or untrusted certificates.

addresses: CWE-295

Correct system time is required for proper enforcement of certificate notBefore/notAfter dates and time-based revocation checks.

References