CVE-2016-8786

Vulnerability

The vulnerability is a denial of service (DoS) in multiple Huawei switches (S12700, S5700, S6700, S7700, S9700) running specific firmware versions. Due to lack of input validation, a remote attacker can craft a malformed Resource Reservation Protocol (RSVP) packet and send it to the device, causing buffer overflows and occasional device restart. Affected versions include S12700 V200R005C00, V200R006C00, V200R007C00, V200R008C00; S5700 V200R006C00, V200R007C00, V200R008C00; S6700 V200R008C00; S7700 V200R001C00, V200R002C00, V200R003C00, V200R005C00, V200R006C00, V200R007C00, V200R008C00; S9700 V200R001C00, V200R002C00, V200R003C00, V200R005C00, V200R006C00, V200R007C00, V200R008C00. [1]

Exploitation

An attacker needs network access to send RSVP packets to the targeted device. No authentication is required. The attacker crafts a malformed RSVP packet and transmits it to the device. The lack of input validation in the RSVP processing code leads to a buffer overflow, which can cause the device to restart. [1]

Impact

Successful exploitation results in a denial of service (DoS) due to device restart. The impact is temporary loss of network services provided by the affected switch. No code execution or data compromise is indicated. [1]

Mitigation

Huawei has released software updates to fix this vulnerability. Affected users should upgrade to the resolved versions as specified in the security advisory. For example, S12700 should be upgraded to V200R009C00SPC500, and similar upgrades are available for other models. The advisory was released on 2016-12-28. No workarounds are mentioned. [1]