CVE-2023-29001: Contiki-NG is an open-source, cross-platform operating system for IoT devices.

Contiki-NG is an open-source, cross-platform operating system for IoT devices.

Contiki-NG is an open-source, cross-platform operating system for IoT devices. The Contiki-NG operating system processes source routing headers (SRH) in its two alternative RPL protocol implementations. The IPv6 implementation uses the results of this processing to determine whether an incoming packet should be forwarded to another host. Because of missing validation of the resulting next-hop address, an uncontrolled recursion may occur in the tcpip_ipv6_output function in the os/net/ipv6/tcpip.c module when receiving a packet with a next-hop address that is a local address. Attackers that have the possibility to send IPv6 packets to the Contiki-NG host can therefore trigger deeply nested recursive calls, which can cause a stack overflow. The vulnerability has not been patched in the current release of Contiki-NG, but is expected to be patched in the next release. The problem can be fixed by applying the patch in Contiki-NG pull request #2264. Users are advised to either apply the patch manually or to wait for the next release. There are no known workarounds for this vulnerability.

Description from the National Vulnerability Database, published by GitHub

What it means for a small business

If your business uses contiki-ng, install the vendor's update. If you're not sure whether you use it, ask whoever manages your computers.

How likely is an attack? The Exploit Prediction Scoring System, run by FIRST (the global association of security response teams), puts the odds of this one being exploited in the next 30 days at 0.56%, higher than 46% of CVEs. That’s low, but low isn’t zero, and the odds jump the day someone publishes an exploit. Scored October 28, 2026, updated daily.

Check your own setup

Website check: reads what your site runs from the outside (WordPress version, plugins it can see, old server software) and matches it against this database.
Server check: what your web server says about itself, and whether that version has known flaws.

Sources

Part of the Huttenlocher Technologies vulnerability database, refreshed twice a day from CISA and the NVD. The title, category and plain-language guidance are ours; check the linked record before acting on a detail. This is general guidance, not a review of your systems.

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