SB2019091127 - Multiple vulnerabilities in Siemens SCALANCE W-700 (IEEE 802.11n)

Description

This security bulletin contains information about 3 secuirty vulnerabilities.

1) Resource exhaustion (CVE-ID: CVE-2019-11479)

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

The vulnerability exists due to presence of hard-coded MSS value (48 bytes) in the Linux kernel source code. A remote attacker can fragment TCP resend queues significantly more than if a larger MSS were enforced and perform denial of service (DoS) attack.

2) Integer overflow (CVE-ID: CVE-2019-11477)

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

The vulnerability exists due to integer overflow when handling TCP Selective Acknowledgments (SACKs) due to incorrect processing of TCP_SKB_CB(skb)->tcp_gso_segs value in Linux kernel. A remote non-authenticated attacker can send specially crafted network traffic to the affected system, trigger integer overflow and render the system unavailable.

Successful exploitation of the vulnerability allows a remote attacker to perform denial of service (DoS) attack.

3) Resource exhaustion (CVE-ID: CVE-2019-11478)

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

The vulnerability exists due to an error when processing TCP Selective Acknowledgment (SACK) sequences within the Linux kernel TCP retransmission queue implementation in tcp_fragment. A remote non-authenticated attacker can send specially crafted network traffic to the affected system and perform a denial of service (DoS) attack.

Remediation

Cybersecurity Help is not aware of any official remediation provided by the vendor.

References

• https://ics-cert.us-cert.gov/advisories/icsa-19-253-03