CVE-2021-21379

CVE-2021-21379 is a high-severity vulnerability in Xwiki with a CVSS 3.x base score of 7.7. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-281.

Key facts

Description

XWiki Platform is a generic wiki platform offering runtime services for applications built on top of it. In affected versions of XWiki Platform, 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. This vulnerability has been patched in versions XWiki 12.6.3, 11.10.11 and 12.8-rc-1. 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.

Frequently asked questions

What is CVE-2021-21379?
XWiki Platform is a generic wiki platform offering runtime services for applications built on top of it. In affected versions of XWiki Platform, 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. This vulnerability has been patched in versions XWiki 12.6.3, 11.10.11 and 12.8-rc-1. 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.
How severe is CVE-2021-21379?
CVE-2021-21379 has a CVSS 3.x base score of 7.7, rated high severity. It is exploitable over network with high attack complexity, requires low privileges and user interaction. Impact on confidentiality is high, integrity high, and availability none.
Is CVE-2021-21379 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (37th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-21379?
CVE-2021-21379 affects Xwiki. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-21379?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-21379 published?
CVE-2021-21379 was published on 2021-03-12 and last updated on 2026-06-17.

References

Affected products (1)

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