The vulnerability in the MSC800 in all versions before 4.15 allows for an attacker to predict the TCP initial sequence number.

published 2022-04-11 4 y ago modified 2026-06-17 4 mo ago also EUVD-2022-32078

cvss: 9.1; version 3.1, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 1.4%; EPSS 1.4% chance of exploitation in 30 days, percentile 73%
public exploits: 0; none known

The vulnerability in the MSC800 in all versions before 4.15 allows for an attacker to predict the TCP initial sequence number. When the TCP sequence is predictable, an attacker can send packets that are forged to appear to come from a trusted computer. These forged packets could compromise services on the MSC800. SICK has released a new firmware version of the SICK MSC800 and recommends updating to the newest version.

Patch / fix

fixed in 1

sick msc800_firmware 4.15

Exploit prediction

1.44% chance of exploitation in the next 30 days, higher than 73% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
NVD	3.1	9.1	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
NVD	2.0	6.4	AV:N/AC:L/Au:N/C:P/I:N/A:P

Affected products

n/a SICK MSC800

Classification

Weakness

CWE-342 Predictable Exact Value from Previous Values
CWE-330 Use of Insufficiently Random Values

References

sick.com /psirt
vendor-advisory

Sources

CVE List CVE-2022-27577
NVD CVE-2022-27577

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Summary