CVE-2026-5720: miniupnpd Integer Underflow SOAPAction Header Parsing
Last updated 7 September 2026
Other sources
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.
— NVD
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
debian/miniupnpdto a version that resolves this vulnerability.Fixed in 2.3.9-2+deb13u1Fixed in 2.3.10-1
Event History
Frequently Asked Questions
What is the severity of CVE-2026-5720?
CVE-2026-5720 has been classified as a high severity vulnerability due to its potential to cause denial of service and information disclosure.
How do I fix CVE-2026-5720?
To mitigate CVE-2026-5720, updating to the latest version of miniupnpd that addresses the integer underflow vulnerability is recommended.
What types of attacks can exploit CVE-2026-5720?
CVE-2026-5720 can be exploited by remote attackers through malformed SOAPAction headers, leading to denial of service or revealing sensitive information.
Which software is affected by CVE-2026-5720?
CVE-2026-5720 affects the MiniUPnP miniupnpd software.
What is the nature of the vulnerability in CVE-2026-5720?
CVE-2026-5720 involves an integer underflow in SOAPAction header parsing, enabling remote code execution and denial of service.