odhcpd is the DHCPv6, DHCPv4, and router-advertisement server used by OpenWrt. In versions 25.12 and prior, odhcpd's DHCPv6 self-loop detection at dhcpv6.c:720 uses a network-byte-order DUID length value directly as the memcmp() size parameter. On little-endian hosts, this causes memcmp() to read far beyond the stack buffer — a single unauthenticated DHCPv6 packet triggers a 2560-byte overread from a 128-byte buffer. At time of publication, there are no publicly available patches.
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Affected Vendors & Products
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History
Fri, 23 Oct 2026 23:45:00 +0000
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Openwrt
Openwrt odhcpd |
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| Vendors & Products |
Openwrt
Openwrt odhcpd |
Fri, 23 Oct 2026 13:30:00 +0000
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| Description | odhcpd is the DHCPv6, DHCPv4, and router-advertisement server used by OpenWrt. In versions 25.12 and prior, odhcpd's DHCPv6 self-loop detection at dhcpv6.c:720 uses a network-byte-order DUID length value directly as the memcmp() size parameter. On little-endian hosts, this causes memcmp() to read far beyond the stack buffer — a single unauthenticated DHCPv6 packet triggers a 2560-byte overread from a 128-byte buffer. At time of publication, there are no publicly available patches. | |
| Title | odhcpd: Stack buffer overread via DUID length endianness mismatch in memcmp() | |
| Weaknesses | CWE-126 | |
| References |
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| Metrics |
cvssV3_1
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Status: PUBLISHED
Assigner: GitHub_M
Published: 2026-10-23T13:21:21.038Z
Updated: 2026-10-23T13:21:21.038Z
Reserved: 2026-06-16T23:31:22.445Z
Link: CVE-2026-55606
No data.
Status : Deferred
Published: 2026-10-23T14:17:53.850
Modified: 2026-10-23T19:37:11.060
Link: CVE-2026-55606
No data.