CVE-2026-5720

Publication date 17 April 2026

Last updated 10 July 2026

Ubuntu priority

Cvss 3 Severity Score

Description

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.

Status

Show unmaintained releases

Package	Ubuntu Release	Status
miniupnpd	26.04 LTS resolute	Needs evaluation
	25.10 questing	Ignored end of life, was needs-triage
	24.04 LTS noble	Needs evaluation
	22.04 LTS jammy	Needs evaluation
	20.04 LTS focal	Needs evaluation
	18.04 LTS bionic	Needs evaluation
	16.04 LTS xenial	Ignored end of ESM support, was needs-triage

Severity score breakdown

CVSS version:

Base score 7.1 · High

Base metrics

Parameter	Value
Attack vector	Adjacent
Attack complexity	Low
Attack requirements	None
Privileges required	None
User interaction	None
Vulnerable system - Confidentiality impact	Low
Vulnerable system - Integrity impact	None
Vulnerable system - Availability impact	High
Subsequent system - Confidentiality impact	None
Subsequent system - Integrity impact	None
Subsequent system - Availability impact	None

Scores

Parameter	Value
Base score	7.1 · High
Base + Threat score	-
Base + Environmental score	-
Base + Threat + Environmental score	-

Vector: CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N

Base score 9.1 · Critical