PT-2026-33521 · Miniupnp · Miniupnpd

Kazuma Matsumoto · Published 2026-04-17 · Updated 2026-04-17 · CVE-2026-5720

Mitre

CVSS v4.0

7.1

High

AV:A/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N

miniupnpd contains an integer underflow vulnerability in SOAPAction header parsing that allows remote attackers to cause a denial of service or information disclosure by sending a malformed SOAPAction header with a single quote. Attackers can trigger an out-of-bounds memory read by exploiting improper length validation in ParseHttpHeaders(), where the parsed length underflows to a large unsigned value when passed to memchr(), causing the process to scan memory far beyond the allocated HTTP request buffer.

Fix

Integer Underflow

Out of bounds Read

Weakness Enumeration

CWE-191

CWE-125

Related Identifiers

CVE-2026-5720

Affected Products

Miniupnpd

References · 4

• https://nvd.nist.gov/vuln/detail/CVE-2026-5720 · Security Note
• https://github.com/miniupnp/miniupnp · Note
• https://github.com/miniupnp/miniupnp/commit/a0ee71e9fa66b60052bb3d2cf84380b79db3f8c8 · Note
• https://vulncheck.com/advisories/miniupnpd-integer-underflow-soapaction-header-parsing · Note