5.4

CVE-2021-21340: Cross-Site Scripting in Content Preview

Modified
Published 23-03-2021Last modified 03-08-2024

Vulnerability summary

CVE-2021-21340 is a medium (CVSS 5.4) vulnerability in typo3. EPSS estimates a 0.87% chance of exploitation in the next 30 days, higher than 58.9% of scored vulnerabilities.

Priority
Routine

Not severe (CVSS 5.4, network access); no exploitation reported by the 5 checked sources

Source freshness unavailable

How is this decided?
CVSS score
5.4/10
010
Medium · v3.1 (CVE.org)
EPSS score
0.87%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded

Timeline

  1. 23-03-2021
    PublishedVulnerability first disclosed.
  2. 03-08-2024
    Last modifiedVulnerability information updated.

Description

TYPO3 is an open source PHP based web content management system. In TYPO3 before versions 10.4.14, 11.1.1 it has been discovered that database fields used as _descriptionColumn_ are vulnerable to cross-site scripting when their content gets previewed. A valid backend user account is needed to exploit this vulnerability. This is fixed in versions 10.4.14, 11.1.1 .

CVSS metrics

3 scores · 2 sources · 2 versions

EPSS trend

Probability

0.87%

Chance of exploitation in the next 30 days

Percentile

59%

Versus all other CVEs

30-day change

No change 0.00 pp

From 0.87% on 04-10-2026

04-10-202603-11-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Version check

Known conditions: network-reachable, low-privilege account, user interaction (CVSS vector). Other conditions: not stated in public data.

Typo32 products
  • typo3≥ 10.0.0, < 10.4.14 | ≥ 11.0.0, < 11.1.1
  • typo3.cms≥ 10.0.0, ≤ 10.4.13 | ≥ 11.0.0, ≤ 11.1.0

1 vendor · 2 products

References

3 links