CVE-2026-58657 (GCVE-0-2026-58657)

Vulnerability from cvelistv5 – Published: 2026-07-08 13:49 – Updated: 2026-10-08 15:23
VLAI
Title
Grav - Stored CSS Injection via Markdown Image resize() Action
Summary
Grav before 2.0.0 (affected through 2.0.0-rc.9 and the 2.0 branch) contains a stored CSS injection vulnerability in the Markdown image resize() media action. Prior media hardening rejects direct ?style= payloads and unsafe attribute() fallbacks, but the resize() action in Excerpts::processMediaActions() writes caller-controlled values directly into the image's styleAttributes. A lower-privileged content editor who can edit page Markdown can store a crafted image URL with semicolon-delimited CSS declarations in the resize parameters, which are rendered into the final <img style=...> attribute when a higher-privileged reviewer/admin views the page or preview. This does not require JavaScript execution but enables UI redress/overlay and content-manipulation attacks (e.g., a full-viewport fixed overlay). Fixed in 2.0.0.
Severity
4.8 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N
4.8 (Medium)
CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-08 14:21 UTC
CWE
  • CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Assigner
VulnCheck CNA
References
Impacted products
Vendor Product Version
Grav Grav Affected: 2.0.0-rc.9 , < 2.0.0 (semver)
Unaffected: 2.0.0 (semver)
    cpe:2.3:a:getgrav:grav:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-06-22 00:00
Credits
DavidCarliez
Show details on NVD website
To clipboard 

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