9.1

CVE-2021-31889: siemens capital embedded ar classic 431-422 Integer Underflow (Wrap or Wraparound)

CVSS: 9.1v3.1CriticalModified
Published 09-11-2021Last modified 11-03-2025
Open JSON

Vulnerability summary

CVE-2021-31889 is a critical (CVSS 9.1) Integer Underflow (Wrap or Wraparound) vulnerability in siemens capital embedded ar classic 431-422. EPSS estimates a 2.17% chance of exploitation in the next 30 days, higher than 82% of scored vulnerabilities.

Overall risk
70/100
0100
High · default modelHow is this calculated?
CVSS score
9.1/10
010
Critical · v3.1 (NVD)
EPSS score
2.17%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 09-11-2021
    PublishedVulnerability first disclosed.
  2. 11-03-2025
    Last modifiedVulnerability information updated.

Description

A vulnerability has been identified in Capital Embedded AR Classic 431-422 (All versions), Capital Embedded AR Classic R20-11 (All versions < V2303), PLUSCONTROL 1st Gen (All versions), SIMOTICS CONNECT 400 (All versions < V0.5.0.0). Malformed TCP packets with a corrupted SACK option leads to Information Leaks and Denial-of-Service conditions. (FSMD-2021-0015)

CVSS metrics

3 scores · 2 sources · 2 versions

EPSS trend

Probability

2.17%

Chance of exploitation in the next 30 days

Percentile

82%

Versus all other CVEs

30-day change

0.00 pp

From 2.17% on 18-09-2026

18-09-202618-10-2026
EPSS score
2.17%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Siemens5 products

1 vendor · 5 products

References

10 links