HCE1-SA-2023-0043 Critical HCE 1.1 Security Fix(es): libxml2 20904-GITv2.9.4-16-g0741801 is vulnerable to a heap-based buffer over-read in the xmlDictComputeFastKey function in dict.c. This vulnerability causes programs that use libxml2, such as PHP, to crash. This vulnerability exists because of an incomplete fix for libxml2 Bug 759398. (CVE-2017-9049) libxml2 2.9.4 and earlier, as used in XMLSec 1.2.23 and earlier and other products, does not offer a flag directly indicating that the current document may be read but other files may not be opened, which makes it easier for remote attackers to conduct XML External Entity (XXE) attacks via a crafted document. (CVE-2016-9318) The htmlParseTryOrFinish function in HTMLparser.c in libxml2 2.9.4 allows attackers to cause a denial of service (buffer over-read) or information disclosure. (CVE-2017-8872) 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. (CVE-2017-9048) ** DISPUTED ** libxml2 2.9.4, when used in recover mode, allows remote attackers to cause a denial of service (NULL pointer dereference) via a crafted XML document. NOTE: The maintainer states "I would disagree of a CVE with the Recover parsing option which should only be used for manual recovery at least for XML parser." (CVE-2017-5969) A flaw in libxml2 allows remote XML entity inclusion with default parser flags (i.e., when the caller did not request entity substitution, DTD validation, external DTD subset loading, or default DTD attributes). Depending on the context, this may expose a higher-risk attack surface in libxml2 not usually reachable with default parser flags, and expose content from local files, HTTP, or FTP servers (which might be otherwise unreachable). (CVE-2017-7375) A flaw was found in libxml2. Exponential entity expansion attack its possible bypassing all existing protection mechanisms and leading to denial of service. (CVE-2021-3541) HCE 1.1 libxml2-2.9.1-6.hce1c.9.x86_64.rpm libxml2-devel-2.9.1-6.hce1c.9.x86_64.rpm libxml2-python-2.9.1-6.hce1c.9.x86_64.rpm