CVE-2021-39169

lowpriority · track · 22EPSS 0.007 · 54 %ileEUUS
grimoire priorityP3 · Track
Exploitable?
—
no known exploitation
Likely / severe?
0.74% (54th) EPSS
CVSS 3.5 · low
Is it mine?
2 products
Check your exposure
Who says so?
3 sources
cnnvd · enisa_euvd · nvd

EPSS · scored 2026-10-28

Misskey is a decentralized microblogging platform. In versions of Misskey prior to 12.51.0, malicious actors can use the web client built-in dialog to display a malicious string, leading to cross-site scripting (XSS). XSS could compromise the API request token. This issue has been fixed in version 12.51.0. There are no known workarounds aside from upgrading.

01

cvss

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

8.0
010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · low–high · 3.5–8

v2.03.5lowAV:N/AC:M/Au:S/C:N/I:P/A:Nprimary · NVD / NIST USexploitability 6.8 · impact 2.9
v3.15.4mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:Nprimary · NVD / NIST USexploitability 2.3 · impact 2.7
v3.18highCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:Hsecondary · ENISA EU
v3.18highCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:Hsecondary · security-advisories@github.comexploitability 2.1 · impact 5.9
v3.15mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N/E:Usecondary · CVSS-BT (t0sche)
02

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-79US
03

affected products (2)

Products and version ranges known to be affected.

04

also known as (2)

Other names and identifiers for this entity.

05

sources

Which sources assert this record, and when.

cnnvdenisa_euvdnvdNVDCVE.orgMITRE
published 2021-08-27modified 2026-06-17
06

references (7)

External citations — patches, advisories, analysis.

scry

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