Bug 2525036 (CVE-2026-71401)

Summary: CVE-2026-71401 wicked: wicked: Denial of Service via integer underflow in DHCPv4 packet capture
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedKeywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in wicked, specifically in its DHCPv4 packet capture code. An integer underflow vulnerability exists where the ni_capture_inspect_udp_header() function fails to validate the IP total length field against the IP header length before performing a subtraction. This oversight allows an unauthenticated attacker on the same network to trigger an out-of-bounds read in the wicked DHCPv4 client (wickedd-dhcp4), potentially leading to a daemon crash and a Denial of Service. No information disclosure has been demonstrated as a result of this issue.
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Bug Depends On: 2526702    
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Description OSIDB Bzimport 2026-08-27 16:54:41 UTC 
An integer underflow was found in the DHCPv4 packet capture code of wicked. ni_capture_inspect_udp_header() in src/capture.c does not verify that the IP total length field (ip_len) is at least as large as the IP header length (ihl) before subtracting the header length. An unauthenticated attacker on the same network can thereby trigger an out-of-bounds read past the receive buffer in the wicked DHCPv4 client (wickedd-dhcp4), which can crash the daemon depending on the process memory layout. No information disclosure has been demonstrated. This issue affects wicked up to and including version 0.6.80.