CVE-2026-9658

Plack::Middleware::Security::Common versions before 0.13.1 for Perl did not block header injections in request paths

HIGH
7.3
CVSS Score
Published: May 28, 2026 at 11:36 AM UTC
Updated: October 26, 2026 at 11:10 AM UTC
1 product affected across 1 vendorPlack::Middleware::Security::Common

Using Plack::Middleware::Security::Common by RRWO?

Get instant alerts when new vulnerabilities affect Plack::Middleware::Security::Common - before attackers find them.

Real-time alertsTrack your software stackFree plan available
Severity
HIGH7.3
Exploit prediction
EPSS 0.2%
SSVC
No known exploit

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 0.13.1
Affected range stops below 0.13.1, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet, and no fixed version or vendor advisory is recorded against it.

SSVC — Action Prioritization

SSVCNo known exploitAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

7.3HIGHCISA-ADP
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
LOW
Integrity
LOW
Availability
LOW
Vector?

Quick Info

StatusDEFERRED
CWE
CWE-790CWE-113

Get alerted

Stop reading CVE feeds looking for your own stack

Track the products you run and VulnTracker tells you when a new CVE affects them — with what is known about fixing it, and nothing about the rest.

Free plan, no card