CVE-2016-9941

Heap-based buffer overflow in rfbproto.c in LibVNCClient in LibVNCServer before 0.9.11 allows remote servers to cause a denial of service (application crash) or possibly execute arbitrary code via a crafted FramebufferUpdate message containing a subrectangle outside of the client drawing area.

Heap-based buffer overflow in rfbproto.c in LibVNCClient in LibVNCServer before 0.9.11 allows remote servers to cause a denial of service (application crash) or possibly execute arbitrary code via a crafted FramebufferUpdate message containing a subrectangle outside of the client drawing area.

It was discovered that there were two vulnerabilities in libvncserver, a library to create/embed a VNC server:

A heap-based buffer overflow that allows remote servers to cause a denial of service via a crafted FramebufferUpdate message containing a subrectangle outside of the drawing area (CVE-2016-9941).

A heap-based buffer overflow that allow remote servers to cause a denial of service via a crafted FramebufferUpdate message with the "Ultra" type tile such that the LZO decompressed payload exceeds the size of the tile dimensions (CVE-2016-9942).

LibVNCServer was updated to fix two security issues.

These security issues were fixed:

• CVE-2016-9941: Heap-based buffer overflow in rfbproto.c allowed remote servers to cause a denial of service (application crash) or possibly execute arbitrary code via a crafted FramebufferUpdate message containing a subrectangle outside of the client drawing area (bsc#1017711)
• CVE-2016-9942: Heap-based buffer overflow in ultra.c allowed remote servers to cause a denial of service (application crash) or possibly execute arbitrary code via a crafted FramebufferUpdate message with the Ultra type tile, such that the LZO payload decompressed length exceeds what is specified by the tile dimensions (bsc#1017712)

This update for tigervnc provides the following fixes:

• Prevent malicious server from crashing a server via a buffer overflow, a similar flaw as the LibVNCServer issues CVE-2016-9941 and CVE-2016-9942.. (bsc#1019274)
• CVE-2016-10207: Prevent potential crash due to insufficient clean-up after failure to establish TLS connection. (bsc#1023012)

This update for tigervnc provides the following fixes:

• Prevent malicious server from crashing a server via a buffer overflow, a similar flaw as the LibVNCServer issues CVE-2016-9941 and CVE-2016-9942. (bsc#1019274)
• CVE-2016-10207: Prevent potential crash due to insufficient clean-up after failure to establish TLS connection. (bsc#1023012)

LibVNCServer was updated to fix two security issues.

These security issues were fixed:

• CVE-2018-7225: Missing input sanitization inside rfbserver.c rfbProcessClientNormalMessage() (bsc#1081493).
• CVE-2016-9942: Heap-based buffer overflow in ultra.c allowed remote servers to cause a denial of service (application crash) or possibly execute arbitrary code via a crafted FramebufferUpdate message with the Ultra type tile, such that the LZO payload decompressed length exceeds what is specified by the tile dimensions (bsc#1017712).
• CVE-2016-9941: Heap-based buffer overflow in rfbproto.c allowed remote servers to cause a denial of service (application crash) or possibly execute arbitrary code via a crafted FramebufferUpdate message containing a subrectangle outside of the client drawing area (bsc#1017711).

Josef Gajdusek discovered that the LibVNCServer client library incorrectly handled certain FrameBufferUpdate messages. If a user were tricked into connecting to a malicious server, an attacker could use this issue to cause a denial of service, or possibly execute arbitrary code. (CVE-2016-9941, CVE-2016-9942)

Nicolas Ruff discovered that iTALC had buffer overflows, divide-by-zero errors and didn't check malloc return values. A remote attacker could use these issues to cause a denial of service or possibly execute arbitrary code. (CVE-2014-6051, CVE-2014-6052, CVE-2014-6053, CVE-2014-6054, CVE-2014-6055)

Josef Gajdusek discovered that iTALC had heap-based buffer overflow vulnerabilities. A remote attacker could used these issues to cause a denial of service or possibly execute arbitrary code. (CVE-2016-9941, CVE-2016-9942)

It was discovered that iTALC had an out-of-bounds write, multiple heap out-of-bounds writes, an infinite loop, improper initializations, and null pointer vulnerabilities. A remote attacker could used these issues to cause a denial of service or possibly execute arbitrary code. (CVE-2018-15127, CVE-2018-20019, CVE-2018-20020, CVE-2018-20021, CVE-2018-20022, CVE-2018-20023, CVE-2018-20024, CVE-2018-20748, CVE-2018-20749, CVE-2018-20750, CVE-2018-7225, CVE-2019-15681)