CVE-2025-34458 identifies a reachable assertion vulnerability (CWE-617) in the Dire Wolf software, specifically within the APRS MIC-E decoder function aprs_mic_e() located in src/decode_aprs.c. Dire Wolf is a popular open-source software modem and APRS (Automatic Packet Reporting System) decoder used widely in amateur radio and emergency communication networks. The vulnerability exists in versions up to and including 1.8, prior to commit 3658a87. When the software processes an AX.25 frame containing a MIC-E message with an empty or truncated comment field, it triggers an assertion that expects a non-empty comment. This assertion is not handled gracefully, causing the process to terminate immediately. This behavior allows a remote attacker to send malformed APRS traffic that crashes the Dire Wolf process, resulting in a denial of service (DoS). The attack vector requires no authentication or user interaction, making it trivially exploitable over the network by anyone able to send APRS frames. The CVSS 4.0 base score is 8.7 (high), reflecting the network attack vector, low complexity, no privileges or user interaction required, and a high impact on availability. No patches or fixes are linked in the provided data, but the vulnerability was resolved after commit 3658a87, indicating that updating to versions including this commit mitigates the issue. There are no known exploits in the wild at the time of publication, but the vulnerability poses a significant risk to systems relying on Dire Wolf for APRS decoding and related communications.

For European organizations, the primary impact is denial of service on systems running vulnerable versions of Dire Wolf. This can disrupt APRS-based communication networks, which are often used by amateur radio operators, emergency responders, and community communication groups. Loss of availability in these systems could hinder situational awareness, emergency coordination, and data reporting. Since the vulnerability can be exploited remotely without authentication, malicious actors could target critical communication nodes to cause outages. This is particularly concerning for organizations involved in disaster response or public safety communications that rely on APRS data. Additionally, repeated exploitation could degrade trust in APRS infrastructure and require costly operational responses. While confidentiality and integrity impacts are not evident, the availability impact alone is significant. The vulnerability could also be leveraged as part of a broader attack chain to disrupt communication channels during critical events.

To mitigate this vulnerability, European organizations should immediately identify all systems running Dire Wolf versions up to 1.8 prior to commit 3658a87. They should upgrade to the latest version of Dire Wolf that includes the fix for this assertion failure. If upgrading is not immediately possible, organizations should consider applying custom patches that handle empty or truncated comment fields safely without triggering assertions. Network-level filtering can be implemented to detect and block malformed AX.25 frames with suspicious MIC-E messages, although this requires deep protocol knowledge and may not be fully effective. Monitoring Dire Wolf process stability and implementing automated restarts can reduce downtime but do not prevent exploitation. Organizations should also engage with the amateur radio community and software maintainers to stay informed about patches and exploit developments. Finally, incorporating this vulnerability into incident response plans for APRS infrastructure will improve preparedness for potential denial of service attacks.