libvncserver

An issue was discovered in LibVNCServer through 0.9.11. rfbProcessClientNormalMessage() in rfbserver.c does not sanitize msg.cct.length, leading to access to uninitialized and potentially sensitive data or possibly unspecified other impact (e.g., an integer overflow) via specially crafted VNC packets.

LibVNCServer versions 0.9.15 and prior (fixed in commit 009008e) contain a heap out-of-bounds read vulnerability in the UltraZip encoding handler that allows a malicious VNC server to cause information disclosure or application crash. Attackers can exploit improper bounds checking in the HandleUltraZipBPP() function by manipulating subrectangle header counts to read beyond the allocated heap buffer.

LibVNCServer versions 0.9.15 and prior (fixed in commit dc78dee) contain null pointer dereference vulnerabilities in the HTTP proxy handlers within httpProcessInput() in httpd.c that allow remote attackers to cause a denial of service by sending specially crafted HTTP requests. Attackers can exploit missing validation of strchr() return values in the CONNECT and GET proxy handling paths to trigger null pointer dereferences and crash the server when httpd and proxy features are enabled.

A NULL pointer dereference flaw was found in the way LibVNCServer before 0.9.9 handled certain ClientCutText message. A remote attacker could use this flaw to crash the VNC server by sending a specially crafted ClientCutText message from a VNC client.

An issue was discovered in LibVNCServer before 0.9.13. Byte-aligned data is accessed through uint32_t pointers in libvncclient/rfbproto.c. NOTE: there is reportedly "no trust boundary crossed.

A divide by zero issue was found to occur in libvncserver-0.9.12. A malicious client could use this flaw to send a specially crafted message that, when processed by the VNC server, would lead to a floating point exception, resulting in a denial of service.

An issue was discovered in LibVNCServer before 0.9.13. Byte-aligned data is accessed through uint16_t pointers in libvncserver/translate.c. NOTE: Third parties do not consider this to be a vulnerability as there is no known path of exploitation or cross of a trust boundary

libvncclient v0.9.13 was discovered to contain a memory leak via the function rfbClientCleanup().

An issue was discovered in LibVNCServer before 0.9.13. libvncserver/scale.c has a pixel_value integer overflow.