CVE-2026-58657
4.8 · MEDIUMOverview
CVE-2026-58657 is a medium-severity vulnerability. It was published on July 8, 2026 and has a CVSS 3.1 base score of 4.8 (MEDIUM).
This vulnerability has a CVSS 3.1 base score of 4.8, rated MEDIUM. It can be exploited remotely over the network. Some level of privileges is required for exploitation.
Technical Description
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.
Remediation
Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
References
Frequently Asked Questions
What is CVE-2026-58657?
CVE-2026-58657 is a medium-severity vulnerability. It was published on July 8, 2026 and has a CVSS 3.1 base score of 4.8 (MEDIUM).
How severe is CVE-2026-58657?
This vulnerability has a CVSS 3.1 base score of 4.8, rated MEDIUM. It can be exploited remotely over the network. Some level of privileges is required for exploitation.
How do I fix or remediate CVE-2026-58657?
Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2026-58657?
CyberStrike's AI-powered security agents can automatically detect CVE-2026-58657 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
AI agents map your attack surface to find vulnerabilities like this one.
Automated penetration testing that runs continuously, not just quarterly.
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