CVE-2021-26035

mediumpriority · track · 24EPSS 0.007 · 54 %ileEUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.72% (54th) EPSS

CVSS 4.3 · medium

Is it mine?

3 products

Who says so?

4 sources

cnnvd · enisa_euvd · nvd · osv

EPSS · scored 2026-10-27

An issue was discovered in Joomla! 3.0.0 through 3.9.27. Inadequate escaping in the rules field of the JForm API leads to a XSS vulnerability.

cvss

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

6.1

010

base score 0–10 · higher = more severe · hover a vector to decode

v2.04.3mediumAV:N/AC:M/Au:N/C:N/I:P/A:Nprimary · NVD / NIST USexploitability 8.6 · impact 2.9

v3.16.1mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:Nprimary · NVD / NIST USexploitability 2.8 · impact 2.7

v3.15.6mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N/E:Usecondary · CVSS-BT (t0sche)

The CWE weakness classes this flaw belongs to.

Products and version ranges known to be affected.

Vendor and ecosystem advisories describing this.

BIT-joomla-2021-26035[20210701] - Core - XSS in JForm Rules field2025-04-03vendor · osvUS
An issue was discovered in Joomla! 3.0.0 through 3.9.27. Inadequate escaping in the rules field of the JForm API leads to a XSS vulnerability.

Other names and identifiers for this entity.

Which sources assert this record, and when.

published 2021-07-07modified 2026-06-17

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External citations — patches, advisories, analysis.

scry

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