CVE-2020-29562 is a medium-severity vulnerability affecting the iconv function in the GNU C Library (glibc) versions 2.30 to 2.32. The iconv function is responsible for converting text between different character encodings. This vulnerability arises when iconv attempts to convert UCS4-encoded text containing an irreversible character. In this scenario, the function fails an internal assertion check within its code path, causing the program to abort unexpectedly. This abrupt termination can lead to a denial of service (DoS) condition, where affected applications or services relying on glibc's iconv functionality may crash or become unavailable. The vulnerability does not impact confidentiality or integrity directly, as it does not allow code execution or data manipulation, but it affects availability by crashing processes. Exploitation requires network access (AV:N) but with high attack complexity (AC:H), low privileges (PR:L), and user interaction (UI:R). The scope is unchanged (S:U), and the impact is limited to availability (A:H) without affecting confidentiality or integrity. No known exploits are reported in the wild, and no official patches are linked in the provided data, though it is likely addressed in later glibc releases. The vulnerability is classified under CWE-617 (Reachable Assertion), indicating that an assertion failure can be triggered by crafted input. This issue is particularly relevant for software that processes UCS4 encoded text and uses iconv for encoding conversions, including various Linux-based systems and applications that rely on glibc.

For European organizations, the primary impact of CVE-2020-29562 is the potential for denial of service in systems that utilize affected versions of glibc for character encoding conversions. This could disrupt critical services, especially those handling text processing, data interchange, or communication protocols involving UCS4 encoding. Industries such as telecommunications, finance, government, and healthcare, which often rely on Linux-based infrastructure, could experience service interruptions or degraded performance. Although the vulnerability does not allow data breaches or code execution, repeated or targeted exploitation could lead to operational downtime, affecting business continuity and service availability. Organizations running legacy or unpatched Linux distributions with glibc versions 2.30 to 2.32 are at risk. Given the medium CVSS score and the requirement for user interaction, the threat is moderate but should not be ignored, especially in environments where high availability is critical.

To mitigate CVE-2020-29562, European organizations should: 1) Identify and inventory systems running glibc versions 2.30 to 2.32, focusing on servers and applications that perform character encoding conversions. 2) Upgrade glibc to a patched version beyond 2.32 where this vulnerability is resolved; consult distribution vendors for security updates or patches. 3) Implement input validation and sanitization to detect and reject malformed or suspicious UCS4 encoded data before it reaches the iconv function. 4) Employ application-level monitoring to detect abnormal process terminations or crashes related to encoding conversions, enabling rapid incident response. 5) Where possible, isolate critical services using containerization or sandboxing to limit the impact of potential DoS conditions. 6) Educate developers and system administrators about the risks of processing untrusted encoding data and the importance of timely patching. 7) Review and update incident response plans to include scenarios involving denial of service due to library assertion failures.