---
id: "CVE-2026-116130"
kind: "vulnerability"
aliases: ["CVE-2026-116130"]
title: "Perl HTTP::Parser::XS: encoded NUL byte truncates request path"
severity: "low"
cvss: null
epss: null
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["http-parser-xs", "package", "perl"]
not_affected_if: ["no-path-based-filtering", "pure-perl-backend"]
published_at: "2026-10-30T13:18:31+00:00"
first_seen_at: "2026-10-30T13:30:27+00:00"
updated_at: "2026-10-30T13:32:31+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-116130", "first_seen_at": "2026-10-30T13:30:27+00:00"}]
---

# Perl HTTP::Parser::XS: encoded NUL byte truncates request path

HTTP::Parser::XS before 0.18 URL-decodes the request path and measures it with strlen(), so PATH_INFO stops at an encoded %00 byte. An attacker can make a proxy or filter check one path while the application routes on a shorter one.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Check the installed version: `perl -MHTTP::Parser::XS -e 'print $HTTP::Parser::XS::VERSION'`
- Find where the project declares HTTP::Parser::XS in its cpanfile, Makefile.PL or lock file
- Check whether the application relies on a proxy or filter path check that runs before the Perl app routes requests

## Fix

- HTTP::Parser::XS: move to `0.18` or later

## Timeline

- 2026-10-30T13:30:27+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-116130

## From the sources

HTTP::Parser::XS versions before 0.18 for Perl truncate PATH_INFO at an encoded NUL byte in parse_http_request.

The XS parser URL-decodes the request path and measures the result with strlen(), so PATH_INFO ends at the first byte decoded from %00. The pure-Perl backend is not affected.

A remote attacker can send a path that a proxy or filter checks in full while the application routes on a shorter one.

---

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