How severe is CVE-2021-21379?

CVE-2021-21379 has a CVSS score of 5.4/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance.

How do I fix CVE-2021-21379?

Update org.xwiki.platform:xwiki-platform-rendering-wikimacro-store to 11.10.11 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-21379 is resolved across your whole dependency graph.

How do I detect CVE-2021-21379 in my Maven dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.xwiki.platform:xwiki-platform-rendering-wikimacro-store, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2021-21379 if there is no patch (or I can't update yet)?

If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

Is CVE-2021-21379 actively exploited in the wild?

No public exploit code has been indexed for CVE-2021-21379 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2021-21379?

CVE-2021-21379 has an EPSS (Exploit Prediction Scoring System) score of 0.5%, placing it in the 41th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2021-21379?

CVE-2021-21379 is classified as CWE-281 (CWE-281). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2021-21379 published, and has it been updated?

CVE-2021-21379 was published on March 12, 2021 and was last updated on October 24, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

☕

☕ Maven

Not in CISA KEV

MEDIUM severity

CVE-2021-21379 — xwiki-platform-rendering-…

MEDIUM

CVE-2021-21379 is a medium-severity (CVSS 5.4) CWE-281 vulnerability in org.xwiki.platform:xwiki-platform-rendering-wikimacro-store. A fix is available for org.xwiki.platform:xwiki-platform-rendering-wikimacro-store — see the affected versions and patch details below.

It's possible to execute anything with the rights of the author of a macro which uses the {{wikimacrocontent}} macro

Also known asGHSA-v662-xpcc-9xf6

Published

Mar 12, 2021

Updated

Oct 24, 2026

Affected

3 pkgs

Patched

3 / 3

Exploits

None indexed

Exploitation data as of Oct 30, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

EPSS Exploitation Probability

via FIRST.org ↗

0.5%probability of exploitation in next 30 days

Lower Risk+0.02%

Lower risk than most CVEs41th percentile — riskier than 41% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

How urgent is this, really

Where this sits among everything scored

Real-World Exposure

3 pkgs affected

☕org.xwiki.platform:xwiki-platform-rendering-wikimacro-store☕org.xwiki.platform:xwiki-platform-rendering-wikimacro-store☕org.xwiki.platform:xwiki-platform-rendering-wikimacro-store

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Maven packages — download data is not available via public APIs for these ecosystems.

Description

Impact

The {{wikimacrocontent}} executes the content with the rights of the wiki macro author instead of the caller of that wiki macro. This makes possible to inject scripts through it and they will be executed with the rights of the wiki macro (very often a user which has Programming rights).

Fortunately, no such macro exists by default in XWiki Standard but one could have been created or installed with an extension.

Patches

It has been patched in versions XWiki 12.6.3, 11.10.11 and 12.8-rc-1.

Workarounds

There is no easy workaround other than disabling the affected macros. Inserting content in a safe way or knowing what is the user who called the wiki macro is not easy.

References

https://jira.xwiki.org/browse/XWIKI-17759

For more information

If you have any questions or comments about this advisory:

Open an issue in Jira XWiki
Email us at our security mailing list

Affected Packages

3 total 3 fixed

Ecosystem	Package	Vulnerable range	Fix
☕Maven	`org.xwiki.platform:xwiki-platform-rendering-wikimacro-store`	≥ 11.4&&< 11.10.11	11.10.11`org.xwiki.platform:xwiki-platform-rendering-wikimacro-store:11.10.11`
☕Maven	`org.xwiki.platform:xwiki-platform-rendering-wikimacro-store`	≥ 12.0&&< 12.6.3	12.6.3`org.xwiki.platform:xwiki-platform-rendering-wikimacro-store:12.6.3`
☕Maven	`org.xwiki.platform:xwiki-platform-rendering-wikimacro-store`	≥ 12.7&&< 12.8	12.8`org.xwiki.platform:xwiki-platform-rendering-wikimacro-store:12.8`

Affected Products

1 product · 3 configurations

Application

xwikixwiki

≥ 12.7 && ≤ 12.7.1

range

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.xwiki.platform:xwiki-platform-rendering-wikimacro-store, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update org.xwiki.platform:xwiki-platform-rendering-wikimacro-store to 11.10.11 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-21379 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

Frequently Asked Questions

### Impact The `{{wikimacrocontent}}` executes the content with the rights of the wiki macro author instead of the caller of that wiki macro. This makes possible to inject scripts through it and they will be executed with the rights of the wiki macro (very often a user which has Programming rights). Fortunately, no such macro exists by default in XWiki Standard but one could have been created or installed with an extension. ### Patches It has been patched in versions XWiki 12.6.3, 11.10.11 and 12.8-rc-1. ### Workarounds There is no easy workaround other than disabling the affected macros

O3 Security · Impact-Aware SCA

Is CVE-2021-21379 in your dependencies?

Find it across Maven, including transitive dependencies.

Scan my dependencies How O3 SCA works

CVSS Score

5.4/10CVSS v3 base

Vector breakdown

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

Required

Scope

Changed

Confidentiality

Low

Integrity

Low

Availability

None

Raw vector

CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

CWE Classification

CWE-281CWE-281

Weaponization

No Nuclei template, Metasploit module or public proof-of-concept found.

OpenSSF Scorecard

Package health score

xwiki-platform

5.6/10

Maintained10/10

Code-Review2/10

Branch-ProtectionN/A

Assessed Oct 26, 2026

Timeline

Disclosed

Mar 12, 2021

Last updated

Oct 24, 2026

Identifiers

CVE-2021-21379

GHSA-v662-xpcc-9xf6

References

Advisorygithub.com · GHSA v662 xpcc 9xf6 Advisoryjira.xwiki.org · XWIKI 17759 Advisorynvd.nist.gov · CVE 2021 21379

Related vulnerabilities

Also affects xwiki-platform-rendering-wikimacro-store

This CVE is medium severity; 1 of 1 other CVE affecting xwiki-platform-rendering-wikimacro-store is rated as high or higher (top: high).

CVE-2025-49581

Same weakness: CWE-281

This CVE is medium severity; 6 of 7 other CVEs with CWE-281 are rated as high or higher (top: high).

CVE-2026-58494CVE-2026-61709CVE-2026-88016CVE-2026-58510CVE-2026-35341CVE-2026-35361CVE-2026-39828Browse all CWE-281

Provenance

Sources

OSV.devNVDFIRST.org (EPSS)

Last verifiedOct 24, 2026

CVE-2021-21379 — xwiki-platform-rendering-…

EPSS Exploitation Probability

How urgent is this, really

Where this sits among everything scored

Real-World Exposure

Description

Impact

Patches

Workarounds

References

For more information

Affected Packages

Affected Products

Detection & mitigation playbook

Detect

Fix

Workarounds

Frequently Asked Questions

Is CVE-2021-21379 in your dependencies?