What is CVE-2021-23856?

CVE-2021-23856 is a critical-severity vulnerability in Bosch Rexroth Indramotion Mlc L20, classified under Cross-site Scripting. CVSS score: 10.0/10. Published 2021-10-04.

How severe is CVE-2021-23856?

Critical severity. CVSS v3 base score is 10.0 out of 10.

XSS in Bosch Rexroth Indramotion Mlc L20

CVE-2021-23856

The web server is vulnerable to reflected XSS and therefore an attacker might be able to execute scripts on a client’s computer by sending the client a manipulated URL.

Vulnerability class: XSS (Cross-Site Scripting)

Published 2021-10-04 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 10.0 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.006 (48.1th percentile), scored 2026-09-29.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 48th percentile — 48.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.006 · newest: 0.006 · change: 0.000

Affected products

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

References

psirt.bosch.com/security-advisories/bosch-sa-741752.html (Vendor Advisory)

Frequently asked questions

What is CVE-2021-23856?: CVE-2021-23856 is a critical-severity vulnerability in Bosch Rexroth Indramotion Mlc L20, classified under Cross-site Scripting. CVSS score: 10.0/10. Published 2021-10-04.
How severe is CVE-2021-23856?: Critical severity. CVSS v3 base score is 10.0 out of 10.