CVE-2026-45615 Details

A memory safety vulnerability has been identified in the OER decoding skeleton files generated by mouse07410/asn1c, specifically in versions 1.4 and earlier. The vulnerability arises when the decoder processes a maliciously crafted, zero-length OER payload for a variable-length, non-negative INTEGER type. The decoder fails to validate the required bytes before extracting the Most Significant Bit (MSB), leading to a precise 1-byte heap out-of-bounds read. This vulnerability can be exploited by remote attackers, causing a denial-of-service (DoS) condition or triggering incorrect integer interpretations in downstream applications, such as protocol state poisoning or logic bypass.

A proposed patch is to implement a validation check in the INTEGER OER decoding function to ensure that the length parameter is greater than zero before extracting the Most Significant Bit. However, this patch should be tested thoroughly to avoid unintended side effects.