CVE-2026-9658
highpriority · track · 0EPSS 0.002 · 13 %ileEUEPSS · scored 2026-10-27
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.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.7–7.3
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (1)
Products and version ranges known to be affected.
also known as (3)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (6)
External citations — patches, advisories, analysis.
- http://www.openwall.com/lists/oss-security/2026/05/28/9cnnvd
- https://access.redhat.com/security/cve/cve-2026-9658cnnvd
- https://metacpan.org/release/RRWO/Plack-Middleware-Security-Simple-v0.13.1/changescnnvd
- https://metacpan.org/release/RRWO/Plack-Middleware-Security-Simple-v0.13.1/changesenisa_euvd
- http://www.openwall.com/lists/oss-security/2026/05/28/9nvd
- https://metacpan.org/release/RRWO/Plack-Middleware-Security-Simple-v0.13.1/changesnvd
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