CVE-2021-30458
Wikimedia Parsoid vulnerable to Cross-site Scripting (XSS)
An issue was discovered in Wikimedia Parsoid before 0.11.1 and 0.12.x before 0.12.2. An attacker can send crafted wikitext that Utils/WTUtils.php will transform by using a <meta> tag, bypassing sanitization steps, and potentially allowing for XSS.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- Required
What an attacker can affect
- Confidentiality
- Low
- Integrity
- Low
- Availability
- None
Exploit likelihood
What each source reports
NVD Score used
6.1
An issue was discovered in Wikimedia Parsoid before 0.11.1 and 0.12.x before 0.12.2. An attacker can send crafted wikitext that Utils/WTUtils.php will transform by using a <meta> tag, bypassing sanitization steps, and potentially allowing for XSS.
- Record
CVE-2021-30458- CVSS 3.1
- 6.1 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N - CVSS 2.0
- 4.3 Medium
AV:N/AC:M/Au:N/C:N/I:P/A:N - Weakness
- CWE-79
- Updated
- 2026-11-02
CVE List No score
An issue was discovered in Wikimedia Parsoid before 0.11.1 and 0.12.x before 0.12.2. An attacker can send crafted wikitext that Utils/WTUtils.php will transform by using a <meta> tag, bypassing sanitization steps, and potentially allowing for XSS.
- Record
CVE-2021-30458- Updated
- 2026-11-02
EUVDEUVD-2022-2633 No score
An issue was discovered in Wikimedia Parsoid before 0.11.1 and 0.12.x before 0.12.2. An attacker can send crafted wikitext that Utils/WTUtils.php will transform by using a <meta> tag, bypassing sanitization steps, and potentially allowing for XSS.
- Record
EUVD-2022-2633- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-5pqx-77vf-85rw
6.1
Wikimedia Parsoid vulnerable to Cross-site Scripting (XSS)
An issue was discovered in Wikimedia Parsoid before 0.11.1 and 0.12.x before 0.12.2. An attacker can send crafted wikitext that Utils/WTUtils.php will transform by using a <meta> tag, bypassing sanitization steps, and potentially allowing for XSS.
- Record
GHSA-5pqx-77vf-85rw- CVSS 3.1
- 6.1 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N - Weakness
- CWE-79
- Updated
- 2026-11-02
OSV
6.1
An issue was discovered in Wikimedia Parsoid before 0.11.1 and 0.12.x before 0.12.2. An attacker can send crafted wikitext that Utils/WTUtils.php will transform by using a <meta> tag, bypassing sanitization steps, and potentially allowing for XSS.
- Record
CVE-2021-30458- CVSS 3.1
- 6.1 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N - Updated
- 2026-11-02
OSVDEBIAN-CVE-2021-30458
6.1
An issue was discovered in Wikimedia Parsoid before 0.11.1 and 0.12.x before 0.12.2. An attacker can send crafted wikitext that Utils/WTUtils.php will transform by using a <meta> tag, bypassing sanitization steps, and potentially allowing for XSS.
- Record
DEBIAN-CVE-2021-30458- CVSS 3.1
- 6.1 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N - Updated
- 2026-11-02
OSVGHSA-5pqx-77vf-85rw
6.1
Wikimedia Parsoid vulnerable to Cross-site Scripting (XSS)
An issue was discovered in Wikimedia Parsoid before 0.11.1 and 0.12.x before 0.12.2. An attacker can send crafted wikitext that Utils/WTUtils.php will transform by using a <meta> tag, bypassing sanitization steps, and potentially allowing for XSS.
- Record
GHSA-5pqx-77vf-85rw- CVSS 3.1
- 6.1 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N - Weakness
- CWE-79
- Updated
- 2026-11-02
OSVUBUNTU-CVE-2021-30458
6.1
An issue was discovered in Wikimedia Parsoid before 0.11.1 and 0.12.x before 0.12.2. An attacker can send crafted wikitext that Utils/WTUtils.php will transform by using a <meta> tag, bypassing sanitization steps, and potentially allowing for XSS.
- Record
UBUNTU-CVE-2021-30458- CVSS 3.1
- 6.1 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N - Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
wikimedia/parsoidPackagist |
0.12 up to 0.12.2 | 0.12.2 |
wikimedia/parsoidPackagist |
before 0.11.1 | 0.11.1 |
mediawikiDebian:12 |
before 1:1.35.2-1 | 1:1.35.2-1 |
mediawikiDebian:13 |
before 1:1.35.2-1 | 1:1.35.2-1 |
mediawikiDebian:14 |
before 1:1.35.2-1 | 1:1.35.2-1 |
wikimedia/parsoidPackagist |
0.12 up to 0.12.2, plus listed versions v0.12.0v0.12.0-a1v0.12.0-a10v0.12.0-a11v0.12.0-a12 Show 20 moreShow lessv0.12.0-a13v0.12.0-a14v0.12.0-a15v0.12.0-a16v0.12.0-a17v0.12.0-a18v0.12.0-a19v0.12.0-a2v0.12.0-a20v0.12.0-a21v0.12.0-a22v0.12.0-a23v0.12.0-a3v0.12.0-a4v0.12.0-a5v0.12.0-a6v0.12.0-a7v0.12.0-a8v0.12.0-a9v0.12.1 |
0.12.2 |
wikimedia/parsoidPackagist |
before 0.11.1, plus listed versions v0.11.0 |
0.11.1 |
mediawikiUbuntu:18.04:LTS |
All versions, plus listed versions 1:1.27.3-11:1.27.4-11:1.27.4-21:1.27.4-3 |
None known |
mediawikiUbuntu:Pro:20.04:LTS |
All versions, plus listed versions 1:1.31.2-1ubuntu11:1.31.5-11:1.31.5-1ubuntu11:1.31.5-21:1.31.5-3 Show 4 moreShow less1:1.31.5-3ubuntu11:1.31.6-11:1.31.7-11:1.31.7-1ubuntu0.1~esm1 |
None known |
mediawikiUbuntu:Pro:22.04:LTS |
All versions, plus listed versions 1:1.35.3-11:1.35.4-11:1.35.5-11:1.35.5-1ubuntu11:1.35.5-1ubuntu21:1.35.5-1ubuntu31:1.35.6-11:1.35.6-1ubuntu0.1~esm1 |
None known |
Show 4 moreShow less
| Package | Affected | Fixed |
|---|---|---|
mediawikiUbuntu:Pro:24.04:LTS |
All versions, plus listed versions 1:1.39.4-21:1.39.5-11:1.39.6-11:1.39.7-11:1.39.7-1ubuntu0.1~esm1 |
None known |
mediawikiUbuntu:25.10 |
All versions, plus listed versions 1:1.43.1+dfsg-11:1.43.1+dfsg-21:1.43.3+dfsg-1 |
None known |
mediawikiUbuntu:26.10 |
All versions, plus listed versions 1:1.43.8+dfsg-21:1.43.9+dfsg-11:1.43.9+dfsg-1ubuntu1 |
None known |
mediawikiUbuntu:26.04:LTS |
All versions, plus listed versions 1:1.43.3+dfsg-11:1.43.5+dfsg-11:1.43.6+dfsg-21:1.43.8+dfsg-11:1.43.8+dfsg-2 |
None known |
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-30458 is a medium vulnerability (CVSS 6.1) in Wikimedia Parsoid, published April 9, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.98%, the 62nd percentile. Fixed in wikimedia/parsoid 0.12.2.