vulntracker.iovulntracker.io
© 2026 vulntracker.io

CVE-2021-25978

Apostrophe - XSS

MEDIUM
5.4
CVSS Score
Published: November 7, 2021 at 05:15 PM UTC
Updated: June 17, 2026 at 03:42 AM UTC
2 products affected across 2 vendorsApostrophecmsApostrophecms

Using Apostrophe by Apostrophe?

Get instant alerts when new vulnerabilities affect Apostrophe - before attackers find them.

Real-time alertsTrack your software stackFree plan available
Start FreeSign In
Severity
MEDIUM5.4
Exploit prediction
EPSS 0.5%
SSVC
No known exploit

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

Apostrophecms· Apostrophecms
95%
2.63.0 ≤ v ≤ 3.3.1
Apostrophecms· Apostrophe
60%
v ≥ 2.63.0v ≤ 3.3.12.63.0

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

Patch and advisory references

References (1)

x_refsource_MISCPatchThird Party Advisory
Source: [email protected]
https://github.com/apostrophecms/apostrophe/commit/c8b94ee9c79468f1ce28e31966cb0e0839165e59

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

5.4MEDIUMMend
Attack Vector
NETWORK
Complexity
LOW
Privileges
LOW
User Interaction
REQUIRED
Scope
CHANGED
Confidentiality
LOW
Integrity
LOW
Availability
NONE
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-79

Get alerted

Stop reading CVE feeds looking for your own stack

Track the products you run and VulnTracker tells you when a new CVE affects them — with what is known about fixing it, and nothing about the rest.

Create accountSign in
Free plan, no card