CVE-2026-56113
dhcpcd Heap Use-After-Free in dhcp6_deprecateaddrs via DHCPv6 RENEW
CVSS Score
5.3
EPSS Score
0.0%
EPSS Percentile
0th
dhcpcd through 10.3.2, fixed in commit 5733d3c, contains a heap use-after-free vulnerability that allows unauthenticated same-link attackers to crash the daemon by sending a crafted DHCPv6 RENEW reply with RFC6603 OPTION_PD_EXCLUDE and both preferred and valid lifetimes set to zero. Attackers acting as or impersonating a DHCPv6 server can trigger dhcp6_deprecatedele() to free a delegated child address while an outer TAILQ_FOREACH_SAFE iterator in dhcp6_deprecateaddrs() still holds the freed pointer, causing a use-after-free when TAILQ_REMOVE is reached.
| CWE | CWE-416 |
| Vendor | networkconfiguration |
| Product | dhcpcd |
| Published | Jun 23, 2026 |
| Last Updated | Jun 23, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H Attack Vector
Adjacent
Attack Complexity
High
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High
Affected Versions
NetworkConfiguration / dhcpcd
0 ≤ 10.3.2
References
Credits
CuB3y0nd VulnCheck