CVE-2017-9048: Xmlsoft LIBXML2

High severity, CVSS 7.5. EPSS: 4.8% chance of exploitation in the next 30 days.

libxml2 20904-GITv2.9.4-16-g0741801 is vulnerable to a stack-based buffer overflow. The function xmlSnprintfElementContent in valid.c is supposed to recursively dump the element content definition into a char buffer 'buf' of size 'size'. At the end of the routine, the function may strcat two more characters without checking whether the current strlen(buf) + 2 < size. This vulnerability causes programs that use libxml2, such as PHP, to crash.

Affected products

• Xmlsoft LIBXML2: version 2.9.4 only

Published 2017-05-18. Last modified 2026-06-17.