CVE-2019-20839

libvncclient/sockets.c in LibVNCServer before 0.9.13 has a buffer overflow via a long socket filename.

LibVNCServer is a C library that enables you to implement VNC server functionality into own programs.

Security Fix(es):

• libvncserver: uninitialized memory contents are vulnerable to Information Leak (CVE-2018-21247)

• libvncserver: buffer overflow in ConnectClientToUnixSock() (CVE-2019-20839)

• libvncserver: libvncserver/rfbregion.c has a NULL pointer dereference (CVE-2020-14397)

• libvncserver: libvncclient/rfbproto.c does not limit TextChat size (CVE-2020-14405)

• libvncserver: libvncserver/rfbserver.c has a divide by zero which could result in DoS (CVE-2020-25708)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Additional Changes:

For detailed information on changes in this release, see the Rocky Linux 8.4 Release Notes linked from the References section.

libvncclient/sockets.c in LibVNCServer before 0.9.13 has a buffer overflow via a long socket filename.

LibVNCServer is a C library that enables you to implement VNC server functionality into own programs.

Security Fix(es):

• libvncserver: uninitialized memory contents are vulnerable to Information Leak (CVE-2018-21247)

• libvncserver: buffer overflow in ConnectClientToUnixSock() (CVE-2019-20839)

• libvncserver: libvncserver/rfbregion.c has a NULL pointer dereference (CVE-2020-14397)

• libvncserver: libvncclient/rfbproto.c does not limit TextChat size (CVE-2020-14405)

• libvncserver: libvncserver/rfbserver.c has a divide by zero which could result in DoS (CVE-2020-25708)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Additional Changes:

For detailed information on changes in this release, see the AlmaLinux Release Notes linked from the References section.

Updated libvncserver packages fix security vulnerabilities:

libvncclient/sockets.c in LibVNCServer had a buffer overflow via a long socket filename (CVE-2019-20839).

libvncserver/rfbregion.c had a NULL pointer dereference (CVE-2020-14397).

Byte-aligned data was accessed through uint32_t pointers in libvncclient/rfbproto.c (CVE-2020-14399).

Byte-aligned data was accessed through uint16_t pointers in libvncserver/translate.c (CVE-2020-14400).

libvncserver/scale.c had a pixel_value integer overflow (CVE-2020-14401).

libvncserver/corre.c allowed out-of-bounds access via encodings (CVE-2020-14402).

libvncserver/hextile.c allowed out-of-bounds access via encodings (CVE-2020-14403).

libvncserver/rre.c allowed out-of-bounds access via encodings (CVE-2020-14404).

libvncclient/rfbproto.c does not limit TextChat size (CVE-2020-14405).

The libvncserver package has been updated to version 0.9.13, fixing these issues and several others. See the release announcement for details.

This update for LibVNCServer fixes the following issues:

• security update
• added patches fix CVE-2018-21247 [bsc#1173874], uninitialized memory contents are vulnerable to Information leak
  • LibVNCServer-CVE-2018-21247.patch fix CVE-2019-20839 [bsc#1173875], buffer overflow in ConnectClientToUnixSock()
  • LibVNCServer-CVE-2019-20839.patch fix CVE-2019-20840 [bsc#1173876], unaligned accesses in hybiReadAndDecode can lead to denial of service
  • LibVNCServer-CVE-2019-20840.patch fix CVE-2020-14398 [bsc#1173880], improperly closed TCP connection causes an infinite loop in libvncclient/sockets.c
  • LibVNCServer-CVE-2020-14398.patch fix CVE-2020-14397 [bsc#1173700], NULL pointer dereference in libvncserver/rfbregion.c
  • LibVNCServer-CVE-2020-14397.patch fix CVE-2020-14399 [bsc#1173743], Byte-aligned data is accessed through uint32_t pointers in libvncclient/rfbproto.c.
  • LibVNCServer-CVE-2020-14399.patch fix CVE-2020-14400 [bsc#1173691], Byte-aligned data is accessed through uint16_t pointers in libvncserver/translate.c.
  • LibVNCServer-CVE-2020-14400.patch fix CVE-2020-14401 [bsc#1173694], potential integer overflows in libvncserver/scale.c
  • LibVNCServer-CVE-2020-14401.patch fix CVE-2020-14402 [bsc#1173701], out-of-bounds access via encodings.
  • LibVNCServer-CVE-2020-14402,14403,14404.patch fix CVE-2017-18922 [bsc#1173477], preauth buffer overwrite

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

This update for LibVNCServer fixes the following issues:

• security update
• added patches fix CVE-2018-21247 [bsc#1173874], uninitialized memory contents are vulnerable to Information leak
  • LibVNCServer-CVE-2018-21247.patch fix CVE-2019-20839 [bsc#1173875], buffer overflow in ConnectClientToUnixSock()
  • LibVNCServer-CVE-2019-20839.patch fix CVE-2019-20840 [bsc#1173876], unaligned accesses in hybiReadAndDecode can lead to denial of service
  • LibVNCServer-CVE-2019-20840.patch fix CVE-2020-14398 [bsc#1173880], improperly closed TCP connection causes an infinite loop in libvncclient/sockets.c
  • LibVNCServer-CVE-2020-14398.patch fix CVE-2020-14397 [bsc#1173700], NULL pointer dereference in libvncserver/rfbregion.c
  • LibVNCServer-CVE-2020-14397.patch fix CVE-2020-14399 [bsc#1173743], Byte-aligned data is accessed through uint32_t pointers in libvncclient/rfbproto.c.
  • LibVNCServer-CVE-2020-14399.patch fix CVE-2020-14400 [bsc#1173691], Byte-aligned data is accessed through uint16_t pointers in libvncserver/translate.c.
  • LibVNCServer-CVE-2020-14400.patch fix CVE-2020-14401 [bsc#1173694], potential integer overflows in libvncserver/scale.c
  • LibVNCServer-CVE-2020-14401.patch fix CVE-2020-14402 [bsc#1173701], out-of-bounds access via encodings.
  • LibVNCServer-CVE-2020-14402,14403,14404.patch fix CVE-2017-18922 [bsc#1173477], preauth buffer overwrite

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

This update for LibVNCServer fixes the following issues:

• security update
• added patches fix CVE-2018-21247 [bsc#1173874], uninitialized memory contents are vulnerable to Information leak
  • LibVNCServer-CVE-2018-21247.patch fix CVE-2019-20839 [bsc#1173875], buffer overflow in ConnectClientToUnixSock()
  • LibVNCServer-CVE-2019-20839.patch fix CVE-2019-20840 [bsc#1173876], unaligned accesses in hybiReadAndDecode can lead to denial of service
  • LibVNCServer-CVE-2019-20840.patch fix CVE-2020-14398 [bsc#1173880], improperly closed TCP connection causes an infinite loop in libvncclient/sockets.c
  • LibVNCServer-CVE-2020-14398.patch fix CVE-2020-14397 [bsc#1173700], NULL pointer dereference in libvncserver/rfbregion.c
  • LibVNCServer-CVE-2020-14397.patch fix CVE-2020-14399 [bsc#1173743], Byte-aligned data is accessed through uint32_t pointers in libvncclient/rfbproto.c.
  • LibVNCServer-CVE-2020-14399.patch fix CVE-2020-14400 [bsc#1173691], Byte-aligned data is accessed through uint16_t pointers in libvncserver/translate.c.
  • LibVNCServer-CVE-2020-14400.patch fix CVE-2020-14401 [bsc#1173694], potential integer overflows in libvncserver/scale.c
  • LibVNCServer-CVE-2020-14401.patch fix CVE-2020-14402 [bsc#1173701], out-of-bounds access via encodings.
  • LibVNCServer-CVE-2020-14402,14403,14404.patch fix CVE-2017-18922 [bsc#1173477], preauth buffer overwrite

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:

• security update
• added patches fix CVE-2018-21247 [bsc#1173874], uninitialized memory contents are vulnerable to Information leak
  • LibVNCServer-CVE-2018-21247.patch fix CVE-2019-20839 [bsc#1173875], buffer overflow in ConnectClientToUnixSock()
  • LibVNCServer-CVE-2019-20839.patch fix CVE-2019-20840 [bsc#1173876], unaligned accesses in hybiReadAndDecode can lead to denial of service
  • LibVNCServer-CVE-2019-20840.patch fix CVE-2020-14398 [bsc#1173880], improperly closed TCP connection causes an infinite loop in libvncclient/sockets.c
  • LibVNCServer-CVE-2020-14398.patch fix CVE-2020-14397 [bsc#1173700], NULL pointer dereference in libvncserver/rfbregion.c
  • LibVNCServer-CVE-2020-14397.patch fix CVE-2020-14399 [bsc#1173743], Byte-aligned data is accessed through uint32_t pointers in libvncclient/rfbproto.c.
  • LibVNCServer-CVE-2020-14399.patch fix CVE-2020-14400 [bsc#1173691], Byte-aligned data is accessed through uint16_t pointers in libvncserver/translate.c.
  • LibVNCServer-CVE-2020-14400.patch fix CVE-2020-14401 [bsc#1173694], potential integer overflows in libvncserver/scale.c
  • LibVNCServer-CVE-2020-14401.patch fix CVE-2020-14402 [bsc#1173701], out-of-bounds access via encodings.
  • LibVNCServer-CVE-2020-14402,14403,14404.patch fix CVE-2017-18922 [bsc#1173477], preauth buffer overwrite

This update for LibVNCServer fixes the following issues:

• security update fix CVE-2018-21247 [bsc#1173874], uninitialized memory contents are vulnerable to Information leak fix CVE-2019-20839 [bsc#1173875], buffer overflow in ConnectClientToUnixSock() fix CVE-2019-20840 [bsc#1173876], unaligned accesses in hybiReadAndDecode can lead to denial of service fix CVE-2020-14398 [bsc#1173880], improperly closed TCP connection causes an infinite loop in libvncclient/sockets.c fix CVE-2020-14397 [bsc#1173700], NULL pointer dereference in libvncserver/rfbregion.c fix CVE-2020-14399 [bsc#1173743], Byte-aligned data is accessed through uint32_t pointers in libvncclient/rfbproto.c. fix CVE-2020-14400 [bsc#1173691], Byte-aligned data is accessed through uint16_t pointers in libvncserver/translate.c. fix CVE-2020-14401 [bsc#1173694], potential integer overflows in libvncserver/scale.c fix CVE-2020-14402 [bsc#1173701], out-of-bounds access via encodings. fix CVE-2020-14403 [bsc#1173701], out-of-bounds access via encodings. fix CVE-2020-14404 [bsc#1173701], out-of-bounds access via encodings. fix CVE-2017-18922 [bsc#1173477], preauth buffer overwrite

Ramin Farajpour Cami discovered that LibVNCServer incorrectly handled certain malformed unix socket names. A remote attacker could exploit this with a crafted socket name, leading to a denial of service, or possibly execute arbitrary code. (CVE-2019-20839)

It was discovered that LibVNCServer did not properly access byte-aligned data. A remote attacker could possibly use this issue to cause LibVNCServer to crash, resulting in a denial of service. This issue only affected Ubuntu 18.04 LTS and Ubuntu 16.04 LTS. (CVE-2019-20840)

Christian Beier discovered that LibVNCServer incorrectly handled anonymous TLS connections. A remote attacker could possibly use this issue to cause LibVNCServer to crash, resulting in a denial of service. This issue only affected Ubuntu 20.04 LTS. (CVE-2020-14396)

It was discovered that LibVNCServer incorrectly handled region clipping. A remote attacker could possibly use this issue to cause LibVNCServer to crash, resulting in a denial of service. (CVE-2020-14397)

It was discovered that LibVNCServer did not properly reset incorrectly terminated TCP connections. A remote attacker could possibly use this issue to cause an infinite loop, resulting in a denial of service. (CVE-2020-14398)

It was discovered that LibVNCServer did not properly access byte-aligned data. A remote attacker could possibly use this issue to cause LibVNCServer to crash, resulting in a denial of service. (CVE-2020-14399, CVE-2020-14400)

It was discovered that LibVNCServer incorrectly handled screen scaling on the server side. A remote attacker could use this issue to cause LibVNCServer to crash, resulting in a denial of service, or possibly execute arbitrary code. (CVE-2020-14401)

It was discovered that LibVNCServer incorrectly handled encodings. A remote attacker could use this issue to cause LibVNCServer to crash, resulting in a denial of service, or possibly execute arbitrary code. (CVE-2020-14402, CVE-2020-14403, CVE-2020-14404)

It was discovered that LibVNCServer incorrectly handled TextChat messages. A remote attacker could possibly use this issue to cause LibVNCServer to crash, resulting in a denial of service. (CVE-2020-14405)