CVE-2026-53920
Received
Received - Intake
BaseFortify
Vulnerability report for CVE-2026-53920, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-10-23
Last updated on: 2026-10-23
Assigner: GitHub, Inc.
Description
Description
odhcpd is the DHCPv6, DHCPv4, and router-advertisement server used by OpenWrt. From version 17.01.0 to before version 25.12.3, odhcpd's DHCPv6 IA parser accepts an IA_NA or IA_PD option whose body is shorter than struct dhcpv6_ia_hdr, casts the option header to that full structure, and reads ia->iaid before proving that the IA body contains the IAID field. If an unauthenticated network-adjacent client places a zero-length or otherwise short IA option at the end of odhcpd's 8192-byte receive stack buffer, the IAID read crosses from data_buf into adjacent stack memory. The disclosed bytes are then reflected in the DHCPv6 reply IAID; prior ARM validation showed data_buf[8192:8196] disclosing the saved stack canary, and wider stack scans can leak ASLR-useful stack/process contents. This issue has been patched in version 25.12.3.
CVSS Scores
EPSS Scores
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Meta Information
Helpful Resources
Exploitability
CWE
KEV
| CWE ID | Description |
|---|---|
| CWE-201 | The code transmits data to another actor, but a portion of the data includes sensitive information that should not be accessible to that actor. |
| CWE-200 | The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information. |
| CWE-125 | The product reads data past the end, or before the beginning, of the intended buffer. |
| CWE-126 | The product reads from a buffer using buffer access mechanisms such as indexes or pointers that reference memory locations after the targeted buffer. |
