CVE-2022-35926: Out-of-bounds read in IPv6 neighbor solicitation in Contiki-NG

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2022-08-04 · updated 2026-06-17
Weakness: CWE-125

Description

Contiki-NG is an open-source, cross-platform operating system for IoT devices. Because of insufficient validation of IPv6 neighbor discovery options in Contiki-NG, attackers can send neighbor solicitation packets that trigger an out-of-bounds read. The problem exists in the module os/net/ipv6/uip-nd6.c, where memory read operations from the main packet buffer, <code>uip_buf</code>, are not checked if they go out of bounds. In particular, this problem can occur when attempting to read the 2-byte option header and the Source Link-Layer Address Option (SLLAO). This attack requires ipv6 be enabled for the network. The problem has been patched in the develop branch of Contiki-NG. The upcoming 4.8 release of Contiki-NG will include the patch.Users unable to upgrade may apply the patch in Contiki-NG PR #1654.

Affected products

contiki-ng: before 4.8 — fixed in 4.8

How to fix

Upgrade to a fixed version: contiki-ng 4.8. Check the vendor advisory for mitigations.

References

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