CVE-2022-22822

expat (libexpat) is susceptible to a software flaw that causes process interruption. When processing a large number of prefixed XML attributes on a single tag libexpat can terminate unexpectedly due to integer overflow. The highest threat from this vulnerability is to availability confidentiality and integrity.

This is an important rather than a critical vulnerability due to its practical limitations. The flaw arises from unsafe left-shift operations in storeAtts() within libexpat, which, under extreme conditions (e.g., over 2²⁹ prefixed attributes), can lead to undefined behavior, memory mismanagement, and denial-of-service (DoS). However, exploitation requires specially crafted XML payloads several gigabytes in size (~6.5 GiB), which makes remote exploitation unlikely in real-world environments due to common upload limits and resource constraints. There is no evidence of arbitrary code execution, memory corruption leading to privilege escalation, or data leaks.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.