Multiple vulnerabilities in Siemens SCALANCE SC-600

Published: 2019-09-11 | Updated: 2019-09-11
Severity Medium
Patch available YES
Number of vulnerabilities 3
CVE ID CVE-2019-11479
CVE-2019-11477
CVE-2019-11478
CWE ID CWE-400
CWE-190
Exploitation vector Network
Public exploit N/A
Vulnerable software SCALANCE SC-600 Subscribe
Vendor Siemens

Security Advisory

1) Resource exhaustion

Severity: Medium

CVSSv3: 6.5 [CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C] [PCI]

CVE-ID: CVE-2019-11479

CWE-ID: CWE-400 - Uncontrolled Resource Consumption ('Resource Exhaustion')

Description

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.

Mitigation

Install update from vendor's website.

Vulnerable software versions

SCALANCE SC-600: -

CPE External links

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

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

How the attacker can exploit this vulnerability?

The attacker would have to send a specially crafted request to the affected device in order to exploit this vulnerability.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.

2) Integer overflow

Severity: Medium

CVSSv3: 6.5 [CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C] [PCI]

CVE-ID: CVE-2019-11477

CWE-ID: CWE-190 - Integer Overflow or Wraparound

Description

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.

Mitigation

Install update from vendor's website.

Vulnerable software versions

SCALANCE SC-600: -

CPE External links

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

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

How the attacker can exploit this vulnerability?

The attacker would have to send a specially crafted request to the affected device in order to exploit this vulnerability.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.

3) Resource exhaustion

Severity: Medium

CVSSv3: 6.5 [CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C] [PCI]

CVE-ID: CVE-2019-11478

CWE-ID: CWE-400 - Uncontrolled Resource Consumption ('Resource Exhaustion')

Description

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.


Mitigation

Install update from vendor's website.

Vulnerable software versions

SCALANCE SC-600: -

CPE External links

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

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

How the attacker can exploit this vulnerability?

The attacker would have to send a specially crafted request to the affected device in order to exploit this vulnerability.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.