CVE-2018-7225

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.

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.

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 (CVE-2018-7225).

Updated vino packages fix security vulnerabilities:

The rfbProcessClientNormalMessage function in libvncserver/rfbserver.c in LibVNCServer did not properly handle attempts to send a large amount of ClientCutText data, which allowed remote attackers to cause a denial of service (memory consumption or daemon crash) via a crafted message that was processed by using a single unchecked malloc (CVE-2014-6053).

An issue was discovered in LibVNCServer. rfbProcessClientNormalMessage() in rfbserver.c did 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 (CVE-2018-7225).

LibVNC contained a memory leak in VNC server code, which allowed an attacker to read stack memory and could be abused for information disclosure. Combined with another vulnerability, it could be used to leak stack memory and bypass ASLR. This attack appeared to be exploitable via network connectivity (CVE-2019-15681).

The bundled libvncserver code in vino has been patched to fix these issues.

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. (CVE-2018-7225)

LibVNC before commit 502821828ed00b4a2c4bef90683d0fd88ce495de contains heap out-of-bound write vulnerability in server code of file transfer extension that can result remote code execution. (CVE-2018-15127)

LibVNC before commit a83439b9fbe0f03c48eb94ed05729cb016f8b72f contains multiple heap out-of-bound write vulnerabilities in VNC client code that can result remote code execution. (CVE-2018-20019)

LibVNC before commit 7b1ef0ffc4815cab9a96c7278394152bdc89dc4d contains heap out-of-bound write vulnerability inside structure in VNC client code that can result remote code execution. (CVE-2018-20020)

LibVNC before commit c3115350eb8bb635d0fdb4dbbb0d0541f38ed19c contains a CWE-835: Infinite loop vulnerability in VNC client code. Vulnerability allows attacker to consume excessive amount of resources like CPU and RAM. (CVE-2018-20021)

LibVNC before 2f5b2ad1c6c99b1ac6482c95844a84d66bb52838 contains multiple weaknesses CWE-665: Improper Initialization vulnerability in VNC client code that allows attacker to read stack memory and can be abuse for information disclosure. Combined with another vulnerability, it can be used to leak stack memory layout and in bypassing ASLR. (CVE-2018-20022)

LibVNC before 8b06f835e259652b0ff026898014fc7297ade858 contains CWE-665: Improper Initialization vulnerability in VNC Repeater client code that allows attacker to read stack memory and can be abuse for information disclosure. Combined with another vulnerability, it can be used to leak stack memory layout and in bypassing ASLR. (CVE-2018-20023)

LibVNC before commit 4a21bbd097ef7c44bb000c3bd0907f96a10e4ce7 contains null pointer dereference in VNC client code that can result DoS. (CVE-2018-20024)

LibVNC before 0.9.12 contains multiple heap out-of-bounds write vulnerabilities in libvncclient/rfbproto.c. The fix for CVE-2018-20019 was incomplete. (CVE-2018-20748)

LibVNC before 0.9.12 contains a heap out-of-bounds write vulnerability in libvncserver/rfbserver.c. The fix for CVE-2018-15127 was incomplete. (CVE-2018-20749)

LibVNC through 0.9.12 contains a heap out-of-bounds write vulnerability in libvncserver/rfbserver.c. The fix for CVE-2018-15127 was incomplete. (CVE-2018-20750)

LibVNC commit before d01e1bb4246323ba6fcee3b82ef1faa9b1dac82a contains a memory leak (CWE-655) in VNC server code, which allow an attacker to read stack memory and can be abused for information disclosure. Combined with another vulnerability, it can be used to leak stack memory and bypass ASLR. This attack appear to be exploitable via network connectivity. (CVE-2019-15681)

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

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).

This update for LibVNCServer fixes the following issues:

• CVE-2018-7225: Missing input sanitization inside rfbserver.c rfbProcessClientNormalMessage() (bsc#1081493).

It was discovered that LibVNCServer incorrectly handled certain packet lengths. A remote attacker able to connect to a LibVNCServer could possibly use this issue to obtain sensitive information, cause a denial of service, or execute arbitrary code.

It was discovered that an information disclosure vulnerability existed in the LibVNCServer vendored in iTALC when sending a ServerCutText message. An attacker could possibly use this issue to expose sensitive information. (CVE-2019-15681)

It was discovered that the LibVNCServer and LibVNCClient vendored in iTALC incorrectly handled certain packet lengths. A remote attacker could possibly use this issue to obtain sensitive information, cause a denial of service, or 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)

Nicolas Ruff discovered that Vino incorrectly handled large ClientCutText messages. A remote attacker could use this issue to cause the server to crash, resulting in a denial of service. (CVE-2014-6053)

It was discovered that Vino incorrectly handled certain packet lengths. A remote attacker could possibly use this issue to obtain sensitive information, cause a denial of service, or execute arbitrary code. (CVE-2018-7225)

Pavel Cheremushkin discovered that an information disclosure vulnerability existed in Vino when sending a ServerCutText message. An attacker could possibly use this issue to expose sensitive information. (CVE-2019-15681)

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

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

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)