Cyber Resilience

CVE-2021-27771

High

Published: 12 May 2022

Published
12 May 2022
Modified
21 November 2024
KEV Added
Patch
CVSS Score v3.1 8.2 CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:H
EPSS Score 0.0030 54.1th percentile
Risk Priority 17 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-27771 is a high-severity Path Traversal (CWE-22) vulnerability in Hcltech Sametime. Its CVSS base score is 8.2 (High).

Operationally, ranked in the top 45.9% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability details

User SID can be modified resulting in an Arbitrary File Upload or deletion of directories causing a Denial of Service. When interacting in a normal matter with the Sametime chat application, users hold a cookie containing their session ID (SID).…

more

This value is also used when sending chat messages, receiving notifications and/or transferring files.

CWE(s)

Related Threats

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

Affected Assets

hcltech
sametime
11.6

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-434

Requiring identifiable owners for portable devices reduces the attack surface for unrestricted uploads of dangerous file types via anonymous media.

addresses: CWE-434

Dangerous file uploads can be detonated in the chamber to determine malice before any production write or execution occurs.

addresses: CWE-434

Prevents unrestricted writing of arbitrary or malicious firmware by keeping hardware write-protect enabled except under tightly controlled manual procedures.

addresses: CWE-22

Validates pathnames and filenames to prevent traversal outside intended directories.

addresses: CWE-434

Scans files from external sources on download/open/execute, blocking unrestricted uploads of dangerous file types.

References