CVE-2021-3866
lowpriority · track · 22EPSS 0.009 · 59 %ileEUUSgrimoire priorityP3 · Track
Exploitable?
—
no known exploitation
Likely / severe?
0.89% (59th) EPSS
CVSS 3.5 · low
Who says so?
3 sources
cnnvd · enisa_euvd · nvd
EPSS · scored 2026-10-28
Cross-site Scripting (XSS) - Stored in GitHub repository zulip/zulip more than and including 44f935695d452cc3fb16845a0c6af710438b153d and prior to 3eb2791c3e9695f7d37ffe84e0c2184fae665cb6.
01
cvss
Technical severity, 0–10. One row per scoring source.
6.8
010
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · low–medium · 3.5–6.8
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
v3.06.8mediumCVSS:3.0/AV:N/AC:H/PR:H/UI:R/S:C/C:H/I:L/A:Lsecondary · security@huntr.devexploitability 1 · impact 5.3
02
weaknesses
The CWE weakness classes this flaw belongs to.
03
affected products (3)
Products and version ranges known to be affected.
04
also known as (3)
Other names and identifiers for this entity.
05
sources
Which sources assert this record, and when.
06
references (10)
External citations — patches, advisories, analysis.
- https://blog.zulip.com/2022/01/19/cve-2021-3866/cnnvd
- https://github.com/zulip/zulip/commit/3eb2791c3e9695f7d37ffe84e0c2184fae665cb6cnnvd
- https://huntr.dev/bounties/5f48dac5-e112-4b23-bbbf-cc00ba83bcf2cnnvd
- https://nvd.nist.gov/vuln/detail/CVE-2021-3866cnnvd
- https://blog.zulip.com/2022/01/19/cve-2021-3866/enisa_euvd
- https://github.com/zulip/zulip/commit/3eb2791c3e9695f7d37ffe84e0c2184fae665cb6enisa_euvd
- https://huntr.dev/bounties/5f48dac5-e112-4b23-bbbf-cc00ba83bcf2enisa_euvd
- https://blog.zulip.com/2022/01/19/cve-2021-3866/Vendor Advisorynvd
scry
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