CVE-2026-5720

Publication date 17 April 2026

Last updated 7 September 2026


Ubuntu priority

Cvss 3 Severity Score

9.1 · Critical

Score breakdown

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

Package Ubuntu Release Status
miniupnpd 26.04 LTS resolute
Fixed 2.3.9-2ubuntu0.1~esm1
25.10 questing Ignored end of life, was needs-triage
24.04 LTS noble
Fixed 2.3.4-1ubuntu0.1~esm1
22.04 LTS jammy
Fixed 2.2.3-1ubuntu0.1~esm1
20.04 LTS focal
Fixed 2.1-6.1ubuntu0.1~esm1
18.04 LTS bionic
Fixed 2.0.20171212-2ubuntu0.1~esm1
16.04 LTS xenial
Fixed 1.8.20140523-4.1+deb9u2ubuntu0.1~esm1

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Severity score breakdown

CVSS version:

Base score 7.1 · High

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

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H

References

Related Ubuntu Security Notices (USN)

    • USN-8731-1
    • MiniUPnPd vulnerability
    • 7 September 2026

Other references


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