CVE-2026-1005

The vulnerability is an integer underflow in the wolfSSL packet sniffer component when processing TLS Application Data records in AEAD decryption paths for algorithms like AES-GCM, AES-CCM, and ARIA-GCM. The issue occurs because ssl_DecodePacket lacks a length check; a record shorter than the required explicit IV and authentication tag causes a 16-bit length underflow, wrapping to a large value that is then passed to AEAD decryption routines, leading to a heap buffer overflow [1].

An unauthenticated attacker can exploit this remotely by injecting malformed TLS records into network traffic that is being monitored by the wolfSSL packet sniffer. No prior authentication or special network position is required; the attack can be triggered through crafted TLS Application Data packets.

Successful exploitation results in a heap buffer overflow, which can cause a denial-of-service (DoS) crash of the sniffing application. The CVSS score of 5.3 confirms a medium severity, with potential for more severe impact if the overflow allows further memory corruption.

The fix was implemented in pull request #9571 by adding a length check for the sniffer's AEAD decryption path. Users should upgrade wolfSSL to version 5.8.5 or later to mitigate this vulnerability [1].