AWS Common Runtime aws-c-http 0.11.0: HPACK CVE-2026-12043
CVE-2026-12043 Published on June 12, 2026
Heap double-free in AWS Common Runtime aws-c-http
Improper handling of HPACK dynamic table size updates in the AWS Common Runtime aws-c-http library might allow a remote threat actor operating a server to cause memory corruption on a connecting client application, potentially leading to arbitrary code execution, via a crafted sequence of HTTP/2 HEADERS frames.
To remediate this issue, users should upgrade to aws-c-http version 0.11.0.
Vulnerability Analysis
CVE-2026-12043 can be exploited with network access, requires user interaction. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to be very high.
Weakness Type
What is a Double-free Vulnerability?
The product calls free() twice on the same memory address, potentially leading to modification of unexpected memory locations. When a program calls free() twice with the same argument, the program's memory management data structures become corrupted. This corruption can cause the program to crash or, in some circumstances, cause two later calls to malloc() to return the same pointer. If malloc() returns the same value twice and the program later gives the attacker control over the data that is written into this doubly-allocated memory, the program becomes vulnerable to a buffer overflow attack.
CVE-2026-12043 has been classified to as a Double-free vulnerability or weakness.
Products Associated with CVE-2026-12043
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Affected Versions
aws-c-http:- Version 0.4.22, <= 0.10.15 is affected.