CVE-2026-107373: SV read before argument conversion in ExtUtils::Typemaps (Perl)
The CPAN Security Group advisory, published 10 October 2026, describes versions of ExtUtils::Typemaps::STL::String before 1.06 in which the T_STD_STRING typemap may read an SV's size before converting the argument to a string.
Source: CVE-2026-107373: typemap T_STD_STRING pode ler o tamanho de SV antes de converter o argumento (seclists.org). Text prepared with AI from this source.
What happened and what to do
Advisory CVE-2026-107373 was published on 10 October 2026 by the CPAN Security Group on the oss-sec list and affects the ExtUtils-Typemaps-Default distribution in versions before 1.06. The issue lies in the T_STD_STRING typemap: when processing the argument, the code may read an SV's size before converting it to a string. The fix is in version 1.06.
For a company maintaining Perl code with XS extensions, the response starts with an inventory: identifying which projects and build images use the distribution and in which version, including transitive dependencies. Next, upgrade to 1.06 or later, rebuild the affected XS modules and validate them with regression tests. It is also worth auditing where C++ string typemaps are used in your own code and monitoring Perl dependency advisories in an automated pipeline that compares the inventory with vulnerability databases and raises alerts. This is engineering and security process work, not AI.
How the consultancy can help
Exposure diagnosis: we map which Perl services and builds use ExtUtils::Typemaps and in which version. Then we implement the controlled upgrade, rebuild and verification in your environment, with continuous dependency monitoring.
Next step
If your company runs Perl with XS code or CPAN dependencies, send a short description of your environment and receive a scoped proposal for diagnosis and remediation.
Let's assess your project
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