CVE-2019-20788

libvncclient/cursor.c in LibVNCServer through 0.9.12 has a HandleCursorShape integer overflow and heap-based buffer overflow via a large height or width value. NOTE: this may overlap CVE-2019-15690.

Updated libvncserver packages fix security vulnerability:

libvncclient/cursor.c in LibVNCServer through 0.9.12 has a HandleCursorShape integer overflow and heap-based buffer overflow via a large height or width value (CVE-2019-20788).

This update for LibVNCServer fixes the following issues:

• CVE-2019-15690: Fixed a heap buffer overflow (bsc#1160471).
• CVE-2019-15681: Fixed a memory leak which could have allowed to a remote attacker to read stack memory (bsc#1155419).
• CVE-2019-20788: Fixed a integer overflow and heap-based buffer overflow via a large height or width value (bsc#1170441).

This update was imported from the SUSE:SLE-15:Update update project.

These are all security issues fixed in the LibVNCServer-devel-0.9.13-3.1 package on the GA media of openSUSE Tumbleweed.

This update for LibVNCServer fixes the following issues:

• CVE-2019-15690: Fixed a heap buffer overflow (bsc#1160471).
• CVE-2019-15681: Fixed a memory leak which could have allowed to a remote attacker to read stack memory (bsc#1155419).
• CVE-2019-20788: Fixed a integer overflow and heap-based buffer overflow via a large height or width value (bsc#1170441).

This update for LibVNCServer fixes the following issues:

• CVE-2019-15690: Fixed a heap buffer overflow (bsc#1160471).
• CVE-2019-15681: Fixed a memory leak which could have allowed to a remote attacker to read stack memory (bsc#1155419).
• CVE-2019-20788: Fixed a integer overflow and heap-based buffer overflow via a large height or width value (bsc#1170441).

This update for LibVNCServer fixes the following issues:

• CVE-2019-15690: Fixed a heap buffer overflow (bsc#1160471).
• CVE-2019-15681: Fixed a memory leak which could have allowed to a remote attacker to read stack memory (bsc#1155419).
• CVE-2019-20788: Fixed a integer overflow and heap-based buffer overflow via a large height or width value (bsc#1170441).

This update for LibVNCServer fixes the following issues:

• CVE-2019-15690: Fixed a heap buffer overflow (bsc#1160471).
• CVE-2019-15681: Fixed a memory leak which could have allowed to a remote attacker to read stack memory (bsc#1155419).
• CVE-2019-20788: Fixed a integer overflow and heap-based buffer overflow via a large height or width value (bsc#1170441).

It was discovered that LibVNCServer incorrectly handled decompressing data. An attacker could possibly use this issue to cause LibVNCServer to crash, resulting in a denial of service. (CVE-2019-15680)

It was discovered that an information disclosure vulnerability existed in LibVNCServer when sending a ServerCutText message. An attacker could possibly use this issue to expose sensitive information. This issue only affected Ubuntu 19.10, Ubuntu 18.04 LTS, and Ubuntu 16.04 LTS. (CVE-2019-15681)

It was discovered that LibVNCServer incorrectly handled cursor shape updates. If a user were tricked in to connecting to a malicious server, an attacker could possibly use this issue to cause LibVNCServer to crash, resulting in a denial of service, or possibly execute arbitrary code. This issue only affected Ubuntu 19.10, Ubuntu 18.04 LTS, and Ubuntu 16.04 LTS. (CVE-2019-15690, CVE-2019-20788)

It was discovered that LibVNCServer incorrectly handled decoding WebSocket frames. An attacker could possibly use this issue to cause LibVNCServer to crash, resulting in a denial of service, or possibly execute arbitrary code. This issue only affected Ubuntu 19.10, Ubuntu 18.04 LTS, and Ubuntu 16.04 LTS. (CVE-2017-18922)