The version of tigervnc installed on the remote host is prior to 1.12.0 / 1.13.1. It is, therefore, affected by multiple vulnerabilities as referenced in the SSA:2023-317-01 advisory.

  - A vulnerability classified as critical was found in X.org Server. Affected by this vulnerability is the     function _GetCountedString of the file xkb/xkb.c. The manipulation leads to buffer overflow. It is     recommended to apply a patch to fix this issue. The associated identifier of this vulnerability is     VDB-211051. (CVE-2022-3550)

  - A vulnerability, which was classified as problematic, has been found in X.org Server. Affected by this     issue is the function ProcXkbGetKbdByName of the file xkb/xkb.c. The manipulation leads to memory leak. It     is recommended to apply a patch to fix this issue. The identifier of this vulnerability is VDB-211052.
    (CVE-2022-3551)

  - A vulnerability, which was classified as problematic, was found in X.org Server. This affects an unknown     part of the file hw/xquartz/X11Controller.m of the component xquartz. The manipulation leads to denial of     service. It is recommended to apply a patch to fix this issue. The identifier VDB-211053 was assigned to     this vulnerability. (CVE-2022-3553)

  - A vulnerability was found in X.Org. This security flaw occurs because the XkbCopyNames function left a     dangling pointer to freed memory, resulting in out-of-bounds memory access on subsequent XkbGetKbdByName     requests.. This issue can lead to local privileges elevation on systems where the X server is running     privileged and remote code execution for ssh X forwarding sessions. (CVE-2022-4283)

  - A vulnerability was found in X.Org. This security flaw occurs becuase the swap handler for the     XTestFakeInput request of the XTest extension may corrupt the stack if GenericEvents with lengths larger     than 32 bytes are sent through a the XTestFakeInput request. This issue can lead to local privileges     elevation on systems where the X server is running privileged and remote code execution for ssh X     forwarding sessions. This issue does not affect systems where client and server use the same byte order.
    (CVE-2022-46340)

  - A vulnerability was found in X.Org. This security flaw occurs because the handler for the XIPassiveUngrab     request accesses out-of-bounds memory when invoked with a high keycode or button code. This issue can lead     to local privileges elevation on systems where the X server is running privileged and remote code     execution for ssh X forwarding sessions. (CVE-2022-46341)

  - A vulnerability was found in X.Org. This security flaw occurs because the handler for the     XvdiSelectVideoNotify request may write to memory after it has been freed. This issue can lead to local     privileges elevation on systems where the X se (CVE-2022-46342)

  - A vulnerability was found in X.Org. This security flaw occurs because the handler for the     ScreenSaverSetAttributes request may write to memory after it has been freed. This issue can lead to local     privileges elevation on systems where the X server is running privileged and remote code execution for ssh     X forwarding sessions. (CVE-2022-46343)

  - A vulnerability was found in X.Org. This security flaw occurs because the handler for the XIChangeProperty     request has a length-validation issues, resulting in out-of-bounds memory reads and potential information     disclosure. This issue can lead to local privileges elevation on systems where the X server is running     privileged and remote code execution for ssh X forwarding sessions. (CVE-2022-46344)

  - A vulnerability was found in X.Org. This issue occurs due to a dangling pointer in DeepCopyPointerClasses     that can be exploited by ProcXkbSetDeviceInfo() and ProcXkbGetDeviceInfo() to read and write into freed     memory. This can lead to local privilege elevation on systems where the X server runs privileged and     remote code execution for ssh X forwarding sessions. (CVE-2023-0494)

  - A flaw was found in X.Org Server Overlay Window. A Use-After-Free may lead to local privilege escalation.
    If a client explicitly destroys the compositor overlay window (aka COW), the Xserver would leave a     dangling pointer to that window in the CompScreen structure, which will trigger a use-after-free later.
    (CVE-2023-1393)

  - A out-of-bounds write flaw was found in the xorg-x11-server. This issue occurs due to an incorrect     calculation of a buffer offset when copying data stored in the heap in the XIChangeDeviceProperty function     in Xi/xiproperty.c and in RRChangeOutputProperty function in randr/rrproperty.c, allowing for possible     escalation of privileges or denial of service. (CVE-2023-5367)

  - A use-after-free flaw was found in the xorg-x11-server. An X server crash may occur in a very specific and     legacy configuration (a multi-screen setup with multiple protocol screens, also known as Zaphod mode) if     the pointer is warped from within a window on one screen to the root window of the other screen and if the     original window is destroyed followed by another window being destroyed. (CVE-2023-5380)

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

Detections

Analytics

Slackware Linux 15.0 / current tigervnc Multiple Vulnerabilities (SSA:2023-317-01)

high Nessus Plugin ID 185502

Version 1.0