CVE Watch16 oct 2026

CVE-2026-53922

odhcpd is the DHCPv6, DHCPv4, and router-advertisement server used by OpenWrt. In commit cfddd56 and earlier, an unauthenticated host on the

CVSS

6.5

Medio

EPSS

0.3%

p27

KEV

—

Exploit Today

0-100

Publicado: 12 oct 2026 · Última mod.: 16 oct 2026 · CWE-121 · CWE-191

EPSS · 30d

0.3%EPSS · 30 días0.3%

2026-10-132026-10-23

Descripción técnica

odhcpd is the DHCPv6, DHCPv4, and router-advertisement server used by OpenWrt. In commit cfddd56 and earlier, an unauthenticated host on the same link can first obtain two bindings through normal DHCPv6 SOLICIT and REQUEST exchanges and then send a crafted RENEW containing multiple IA_NA options. An earlier matched IA consumes most of the response buffer, an unmatched IA causes the build_ia() status branch to write and return a NOBINDING response larger than the remaining space, and a subsequent matched IA is processed after dhcpv6_ia_handle_IAs() subtracts that over-return from an unsigned size_t. The resulting underflow disables subsequent length checks and permits attacker-controlled IA_ADDR serialization beyond the 512-byte stack buffer pdbuf in handle_client_request(). The stack canary terminates odhcpd, and sustained packets can repeatedly disrupt DHCPv6 service while procd respawns the process. The observed configuration does not establish code execution.

Referencias oficiales

CVEs relacionados

CVECVSSEPSSKEVRExplotTítuloVis.

CVE-2026-1158637.6 ALT

—

———ConnMan through 2.0 has a stack-based buffer overflow via a DHCPv6 Reply message. This occurs in get_domains in gdhcp/client.c. It copies a fixed NS_MAXDNAME (1025) bytes from a DHCPv6 DOMAIN_LIST (option 24) value into a 1026-byte stack buffer dns_name regardless of the actual option length, then walks DNS labels with an unbounded "c += jump + 1" loop. A crafted DHCPv6 REPLY with a DOMAIN_LIST option of >= 1025 non-zero bytes makes the label walk leave the buffer and read/write '.' past its end in attacker-chosen strides. An on-link attacker can trigger this without authentication via a forged Router Advertisement (O=1) and a forged DHCPv6 REPLY matching xid/CLIENTID with a long DOMAIN_LIST. The impact is unauthenticated on-link crash of connmand (runs as root). This was introduced in bb06c47.47m CVE-2026-539219.8 CRÍ

—

———odhcpd is the DHCPv6, DHCPv4, and router-advertisement server used by OpenWrt. Prior to version 25.12, odhcpd's DHCPv6 IA response handler writes past the end of a fixed 512-byte stack buffer (pdbuf) when a single DHCPv6 REQUEST carries enough IA options to nearly exhaust the reply space. Two independent overflow sites exist in the same call chain, both reachable from the network via a single unauthenticated UDP packet. odhcpd runs as root on OpenWrt; embedded targets often lack stack canaries and ASLR, making code execution realistic. This issue has been patched in version 25.12.5h CVE-2026-961857.5 ALT

44.6%

——13Stack-based buffer overflow in Microsoft Exchange Online allows an authorized attacker to execute code over a network.20h CVE-2026-94502—

14.3%

——4In EmberZNet 9.1.1 and earlier, a malformed Publish Price Matrix command can result in an out-of-bounds write potentially leading to remote code execution. These messages must come from a device that has already joined the network. Only devices supporting the Price Cluster are impacted.7h CVE-2026-85080—

27.9%

——8In EmberZNet 9.1.1 and earlier, a malformed GetGroupMembership message can result in an out-of-bounds write leading to a crash. A limited number of values can be written using this vulnerability, so no route to remote code execution was observed. These messages must come from a device that has already joined the network. Only devices supporting the Group Cluster are impacted.7h CVE-2026-85079—

22.1%

——7In EmberZNet 9.1.1 and earlier, a malformed Simple_Desc_req response can result in an out-of-bounds write potentially leading to remote code execution. This response must come from a device that has already joined the network, and the attacker must wait for a Simple_Desc_req before the attack can be performed.1d