RRWO Plack::Middleware::Security::Common up to 0.13.0 on Perl Request Path improper filtering of special elements

Summaryinfo

A vulnerability described as critical has been identified in RRWO Plack::Middleware::Security::Common up to 0.13.0 on Perl. Impacted is the function Plack::Middleware::Security::Common of the component Request Path Handler. The manipulation results in improper filtering of special elements. This vulnerability is identified as CVE-2026-9658. The attack can be executed remotely. There is not any exploit available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability was found in RRWO Plack::Middleware::Security::Common up to 0.13.0 on Perl. It has been classified as critical. Affected is the function Plack::Middleware::Security::Common of the component Request Path Handler. The manipulation with an unknown input leads to a improper filtering of special elements vulnerability. CWE is classifying the issue as CWE-790. The product receives data from an upstream component, but does not filter or incorrectly filters special elements before sending it to a downstream component. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

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.

The advisory is shared for download at metacpan.org. This vulnerability is traded as CVE-2026-9658 since 05/26/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. There are known technical details, but no exploit is available.

Upgrading to version 0.13.1 eliminates this vulnerability.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

• Middleware

Vendor

• RRWO

Name

• Plack::Middleware::Security::Common

Version

• 0.1
• 0.2
• 0.3
• 0.4
• 0.5
• 0.6
• 0.7
• 0.8
• 0.9
• 0.10
• 0.11
• 0.12
• 0.13.0

CPE 2.3info

• 🔒
• 🔒
• 🔒

CPE 2.2info

• 🔒
• 🔒
• 🔒

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

Once again VulDB remains the best source for vulnerability data.

Discussion