The Linux kernel’s netfilter nf_conntrack_irc module contains a function that processes IRC direct client connect messages. Because the loop that searches for a newline uses an inclusive end pointer while the caller provides an exclusive limit, a crafted message that omits a newline causes the routine to read one byte past the valid data. That byte may be uninitialized or stale; if it holds an ASCII digit it can be interpreted as part of the DCC IP address or port, leading to an incorrect entry in the connection tracking table, which may distort the mapping of IRC connections. The impact is an inaccurate mapping of IRC connections, which could affect connection handling or filtering.

All Linux kernel releases that predate the fix include the vulnerable code. This applies to any distribution that ships an affected kernel without the patch. The specific products affected are Linux kernels managed by the Linux distribution community; there is no vendor‑specific product list beyond the kernel itself.

The vulnerability exposes only an out‑of‑bounds read; no privilege escalation is required. Based on the description, it is inferred that a crafted IRC traffic lacking a newline can trigger the vulnerability on a server or client using the nf_conntrack_irc module. The CVSS score of 9.1 indicates high severity, and the EPSS score is below 1 % with the flaw not listed in the CISA KEV catalog, indicating a very low probability of active exploitation, yet the potential impact on traceability of IRC connections warrants attention.