CVE-2021-27771

mediumpriority · track · 30EPSS 0.007 · 54 %ileEUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.73% (54th) EPSS

CVSS 6.5 · medium

Is it mine?

2 products

Check your exposure

Who says so?

3 sources

cnnvd · enisa_euvd · nvd

EPSS · scored 2026-10-27

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.

cvss

Technical severity, 0–10. One row per scoring source.

8.2

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.5–8.2

v2.06.5mediumAV:N/AC:L/Au:S/C:P/I:P/A:Pprimary · NVD / NIST USexploitability 8 · impact 6.4

v3.17.6highCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:Hprimary · NVD / NIST USexploitability 2.8 · impact 4.7

v3.18.2highCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:Hsecondary · ENISA EU

v3.18.2highCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:Hsecondary · psirt@hcl.comexploitability 2.3 · impact 5.3

v3.17highCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:H/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-434USprimaryCWE-22US

affected products (2)

Products and version ranges known to be affected.

HCL Software Sametime≤ 11.6enisa_euvdEU
hcltech sametime= 11.6nvdUScpe:2.3:a:hcltech:sametime:*:*:*:*:*:*:*:*

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd nvd NVD CVE.org MITRE

published 2022-05-12modified 2026-06-17

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+5030 more

references (4)

External citations — patches, advisories, analysis.

scry

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