HCL Sametime is susceptible a file transfer service vulnerability

published 2022-05-12 4 y ago modified 2026-06-17 4 mo ago also EUVD-2021-14512

cvss: 8.2; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.7%; EPSS 0.7% chance of exploitation in 30 days, percentile 54%
public exploits: 0; none known

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

Exploit prediction

0.73% chance of exploitation in the next 30 days, higher than 54% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	8.2	CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:H
NVD	3.1	7.6	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:H
NVD	2.0	6.5	AV:N/AC:L/Au:S/C:P/I:P/A:P

Affected products

HCL Software Sametime

Classification

Weakness

CWE-434 Unrestricted Upload of File with Dangerous Type
CWE-22 Improper Limitation of a Pathname to a Restricted Directory

References

support.hcltechsw.com /csm?id=kb_article&sysparm_article=KB0097430
vendor-advisory

Sources

CVE List CVE-2021-27771
NVD CVE-2021-27771

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary