Rcalvom

**Name of the Vulnerable Software and Affected Versions** Contiki-NG versions 4.9 and prior **Description** Contiki-NG is an operating system for internet-of-things devices. The issue arises during IPHC header decompression when processing IPv6 header fields. Specifically, the system fails to check if the received packet buffer contains enough data before decompressing the IPv6 address, allowing up to 16 bytes to be read out of bounds. This is due to the statement `memcpy(&ipaddr->u8[16 - postcount], iphc ptr, postcount);`, where the value of `postcount` can be controlled by an attacker based on the address compression used in the received packet. As a result, an attacker can inject a packet that causes an out-of-bound read. **Recommendations** For Contiki-NG versions 4.9 and prior, as a temporary workaround, apply the changes in Contiki-NG pull request #2509 to patch the system. At the moment, there is no information about a newer version that contains a fix for this vulnerability.

**Name of the Vulnerable Software and Affected Versions** Contiki-NG versions prior to 4.9 **Description** The issue arises when the Contiki-NG OS processes ICMP DAO packets in the `dao input storing` function without verifying that the packet buffer is sufficiently large, leading to potential out-of-bounds reads of up to 16 bytes. An attacker can exploit this by truncating an ICMP packet, causing the system to access data beyond the buffer's bounds. **Recommendations** For Contiki-NG versions prior to 4.9, apply the changes in Contiki-NG pull request #2435 to patch the system. For version 4.9 and later, no action is required as the issue is expected to be resolved in this release.