CVE-2026-9658
7.3 · HIGHOverview
CVE-2026-9658 is a high-severity vulnerability. It was published on May 28, 2026 and has a CVSS 3.1 base score of 7.3 (HIGH).
This vulnerability has a CVSS 3.1 base score of 7.3, rated HIGH. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
Technical Description
Plack::Middleware::Security::Common versions before 0.13.1 for Perl did not block header injections in request paths.
The header injection rule was ineffective at blocking header injections in the request paths unless they were double-encoded, for example,
GET /path\r\nHTTP/1.1\r\nHost: secret.example.com
Note that it is unclear whether request paths with CRLF followed by additional headers would be blocked by reverse proxies, or how they would be processed by Plack-based servers.
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.
Frequently Asked Questions
What is CVE-2026-9658?
CVE-2026-9658 is a high-severity vulnerability. It was published on May 28, 2026 and has a CVSS 3.1 base score of 7.3 (HIGH).
How severe is CVE-2026-9658?
This vulnerability has a CVSS 3.1 base score of 7.3, rated HIGH. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
How do I fix or remediate CVE-2026-9658?
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-2026-9658?
CyberStrike's AI-powered security agents can automatically detect CVE-2026-9658 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
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