# CVE-2026-107373: ExtUtils::Typemaps::STL::String versions before 1.06 for Perl T_STD_STRING typemap may read the SV length before stringifying the argument.

> An attacker can cause a denial of service via segmentation fault or abort by passing non-string arguments to the T_STD_STRING typemap due to undefined evaluation order.

- **Severity:** Critical 9.1 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 10 Oct 2026
- **Updated:** 16 Oct 2026
- **Also known as:** DEBIAN-CVE-2026-107373, GHSA-g3mm-4ggm-mrv5, UBUNTU-CVE-2026-107373

## What is CVE-2026-107373?

CVE-2026-107373 is a critical memory corruption vulnerability, published on 10 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

ExtUtils::Typemaps::STL::String versions before 1.06 for Perl T_STD_STRING typemap may read the SV length before stringifying the argument.

The typemap uses

    $var = std::string( SvPV_nolen($arg), SvCUR($arg) )

However, evaluation order for C++ arguments is not specified, and some compilers may produce code that evalutes SvCUR($arg) first.

When $arg is not a string (for example, an interger, number or a reference) then SvCUR will return an invalid value, and the program may abort or segfault.

Weakness: CWE-125 (Out-of-bounds Read)

## Which versions are affected by CVE-2026-107373?


## How do I fix CVE-2026-107373?

Upgrade to a fixed version.

## Is CVE-2026-107373 being exploited?

There is no known exploitation of CVE-2026-107373 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-107373 and fix it if it is affected.

What it is: CVE-2026-107373 is a critical memory corruption vulnerability, published on 10 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-107373 in the wild and no public exploit code.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-107373/ (Markdown: https://insights.sbomify.com/CVE-2026-107373/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-107373
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-107373
- OSV: https://osv.dev/vulnerability/CVE-2026-107373

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-107373/
Summaries are generated and may contain mistakes; the official description above is the record.