CVE-2021-25978 - CVE House

Status published Medium CVE-2021-25978

Apostrophe - XSS

5.4 CVSS

Vulnerability Description

Apostrophe CMS versions between 2.63.0 to 3.3.1 are vulnerable to Stored XSS where an editor uploads an SVG file that contains malicious JavaScript onto the Images module, which triggers XSS once viewed.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

The following person or organization is credited with identifying this vulnerability, as recorded in the NVD database:

Daniel Elkabes

References

https://github.com/apostrophecms/apostrophe/commit/c8b94ee9c79468f1ce28e31966cb0e0839165e59

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CVE-2021-25979

Apostrophe - Insufficient Session Expiration

Critical 9.8

Affected Vendor

Apostrophe

View all reports →

Affected Software

Apostrophe

Vulnerable Versions:

unspecified, 2.63.0

Timeline

Official Publish: November 7th, 2021

Last Modified: April 30th, 2025

Added to House: July 21st, 2026

CVSS Vectors

V3: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

Weaknesses (CWE)

CWE-79

MITRE ATT&CK TTPs

T1189 Drive-by Compromise

Initial Access

T1059.007 JavaScript

Execution

T1539 Steal Web Session Cookie

Collection

T1213 Data from Information Repositories