SB2019103107 - Multiple vulnerabilities in TightVNC

Description

This security bulletin contains information about 4 secuirty vulnerabilities.

1) Out-of-bounds write (CVE-ID: CVE-2019-15678)

The vulnerability allows a remote attacker to compromise vulnerable system.

The vulnerability exists due to a boundary error in rfbServerCutText handler when processing untrusted input. A remote attacker can trigger out-of-bounds write and execute arbitrary code on the target system.

2) NULL pointer dereference (CVE-ID: CVE-2019-15680)

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to a NULL pointer dereference error in "zlib.c" in the "HandleZlibBPP" function. A remote attacker can trigger denial of service conditions via network connectivity.

3) Out-of-bounds write (CVE-ID: CVE-2019-15679)

The vulnerability allows a remote attacker to compromise vulnerable system.

The vulnerability exists due to a boundary error in "InitialiseRFBConnection" function. A remote attacker can trigger out-of-bounds write and execute arbitrary code on the target system.

4) Buffer overflow (CVE-ID: CVE-2019-8287)

The vulnerability allows a remote attacker to execute arbitrary code on the target system.

The vulnerability exists due to a boundary error in "corre.c" in the "HandleCoRREBBP" macro function. A remote attacker can trigger memory corruption and execute arbitrary code on the target system.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.

Remediation

Install update from vendor's website.

References

• https://www.openwall.com/lists/oss-security/2018/12/10/5