CVE-2019-19956

xmlParseBalancedChunkMemoryRecover in parser.c in libxml2 before 2.9.10 has a memory leak related to newDoc->oldNs.

Weakness

The product does not sufficiently track and release allocated memory after it has been used, which slowly consumes remaining memory.

Affected Software

Potential Mitigations

• Choose a language or tool that provides automatic memory management, or makes manual memory management less error-prone.
• For example, glibc in Linux provides protection against free of invalid pointers.
• When using Xcode to target OS X or iOS, enable automatic reference counting (ARC) [REF-391].
• To help correctly and consistently manage memory when programming in C++, consider using a smart pointer class such as std::auto_ptr (defined by ISO/IEC ISO/IEC 14882:2003), std::shared_ptr and std::unique_ptr (specified by an upcoming revision of the C++ standard, informally referred to as C++ 1x), or equivalent solutions such as Boost.

References

• http://lists.opensuse.org/opensuse-security-announce/2020-05/msg00047.html
• http://lists.opensuse.org/opensuse-security-announce/2020-06/msg00005.html
• https://cert-portal.siemens.com/productcert/pdf/ssa-292794.pdf
• https://gitlab.gnome.org/GNOME/libxml2/commit/5a02583c7e683896d84878bd90641d8d9b0d0549
• https://lists.debian.org/debian-lts-announce/2019/12/msg00032.html
• https://lists.debian.org/debian-lts-announce/2020/09/msg00009.html
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5R55ZR52RMBX24TQTWHCIWKJVRV6YAWI/
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/JDPF3AAVKUAKDYFMFKSIQSVVS3EEFPQH/
• https://security.netapp.com/advisory/ntap-20200114-0002/
• https://us-cert.cisa.gov/ics/advisories/icsa-21-103-08
• https://usn.ubuntu.com/4274-1/
• https://www.oracle.com/security-alerts/cpujul2020.html