In xsltCopyText in transform.c in libxslt 1.1.33, a pointer variable...

Vulnerability Description

In xsltCopyText in transform.c in libxslt 1.1.33, a pointer variable isn't reset under certain circumstances. If the relevant memory area happened to be freed and reused in a certain way, a bounds check could fail and memory outside a buffer could be written to, or uninitialized data could be disclosed.

References

• https://gitlab.gnome.org/GNOME/libxslt/commit/2232473733b7313d67de8836ea3b29eec6e8e285
• https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=15914
• https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=15768
• https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=15746
• https://usn.ubuntu.com/4164-1/
• https://lists.debian.org/debian-lts-announce/2019/10/msg00037.html
• https://security.netapp.com/advisory/ntap-20191031-0004/
• http://www.openwall.com/lists/oss-security/2019/11/17/2
• http://lists.opensuse.org/opensuse-security-announce/2020-02/msg00010.html
• http://lists.opensuse.org/opensuse-security-announce/2020-02/msg00015.html
• https://access.redhat.com/errata/RHSA-2020:0514
• http://lists.opensuse.org/opensuse-security-announce/2020-02/msg00025.html
• https://www.oracle.com/security-alerts/cpuapr2020.html
• https://security.netapp.com/advisory/ntap-20200416-0004/
• http://lists.opensuse.org/opensuse-security-announce/2020-05/msg00062.html