CVE-2026-55890
Grav: Stored CSS injection via Markdown image ?style=… reaches MediaObjectTrait::style()
Description
Grav is a file-based Web platform. Prior to 2.0.0-rc.9, Grav's incomplete fix for stored XSS through the Markdown media attribute action (CVE-2026-42841) leaves the sibling MediaObjectTrait::style method reachable through the same Markdown excerpt-action pipeline, allowing an editor to save Markdown image style parameters that are written into the rendered img style attribute without sanitization. This issue is fixed in version 2.0.0-rc.9.
INFO
Published Date :
July 10, 2026, 5:17 p.m.
Last Modified :
July 10, 2026, 5:35 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | MEDIUM | [email protected] |
Solution
- Update Grav to version 2.0.0-rc.9 or later.
- Review and sanitize all user-submitted Markdown content.
- Ensure image style parameters are properly validated.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-55890.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-55890 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-55890
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-55890 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-55890 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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New CVE Received by [email protected]
Jul. 10, 2026
Action Type Old Value New Value Added Affected [{'vendor': 'getgrav', 'product': 'grav', 'versions': [{'status': 'affected', 'version': '< 2.0.0-rc.9'}]}] Added Description Grav is a file-based Web platform. Prior to 2.0.0-rc.9, Grav's incomplete fix for stored XSS through the Markdown media attribute action (CVE-2026-42841) leaves the sibling MediaObjectTrait::style method reachable through the same Markdown excerpt-action pipeline, allowing an editor to save Markdown image style parameters that are written into the rendered img style attribute without sanitization. This issue is fixed in version 2.0.0-rc.9. Added CVSS V3.1 AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N Added CWE CWE-79 Added Reference https://github.com/getgrav/grav/commit/24fd6cbc438e12310b126d1176e7d7601203a6f2 Added Reference https://github.com/getgrav/grav/releases/tag/2.0.0-rc.9 Added Reference https://github.com/getgrav/grav/security/advisories/GHSA-pmf8-g7c8-7v54