CVE-2021-36763

In CODESYS V3 web server before 3.5.17.10, files or directories are accessible to External Parties.

Published: 2021-08-03 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-36763 is rated Moderate Risk (51.3/100): CVSS High severity, with medium exploitation likelihood (EPSS 1.01%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2021-36763

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.23% 1.01% +0.78%
2 2026-02-18 0.32% 0.23% -0.09%
3 2025-08-18 — 0.32% —

Full EPSS history (11 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-36763

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
 3.9 3.6 [email protected]
5.0 2.0 MEDIUM
AV:N/AC:L/Au:N/C:P/I:N/A:N Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:N)
No integrity impact.
Availability impact (A:N)
No availability impact.
 10.0 2.9 [email protected]

Weakness enumeration for CVE-2021-36763

Affected software / configurations for CVE-2021-36763

Vendor Product Version Raw CPE
codesys control < 4.2.0.0 cpe:2.3:a:codesys:control:*:*:*:*:*:beaglebone_sl:*:*
codesys control < 4.2.0.0 cpe:2.3:a:codesys:control:*:*:*:*:*:empc-a\/imx6_sl:*:*
codesys control < 4.2.0.0 cpe:2.3:a:codesys:control:*:*:*:*:*:iot2000_sl:*:*
codesys control <= 4.2.0.0 cpe:2.3:a:codesys:control:*:*:*:*:*:linux_sl:*:*
codesys control < 4.2.0.0 cpe:2.3:a:codesys:control:*:*:*:*:*:pfc100_sl:*:*
codesys control < 4.2.0.0 cpe:2.3:a:codesys:control:*:*:*:*:*:pfc200_sl:*:*
codesys control < 4.2.0.0 cpe:2.3:a:codesys:control:*:*:*:*:*:plcnext_sl:*:*
codesys control < 4.2.0.0 cpe:2.3:a:codesys:control:*:*:*:*:*:raspberry_pi_sl:*:*
codesys control < 4.2.0.0 cpe:2.3:a:codesys:control:*:*:*:*:*:wago_touch_panels_600_sl:*:*
codesys control_rte < 3.5.17.10 cpe:2.3:a:codesys:control_rte:*:*:*:*:*:-:*:*
codesys control_rte < 3.5.17.10 cpe:2.3:a:codesys:control_rte:*:*:*:*:*:beckhoff_cx:*:*
codesys control_runtime_system_toolkit < 3.5.17.10 cpe:2.3:a:codesys:control_runtime_system_toolkit:*:*:*:*:*:*:*:*
codesys control_win_sl < 3.5.17.10 cpe:2.3:a:codesys:control_win_sl:*:*:*:*:*:*:*:*
codesys embedded_target_visu_toolkit < 3.5.17.10 cpe:2.3:a:codesys:embedded_target_visu_toolkit:*:*:*:*:*:*:*:*
codesys hmi < 3.5.17.10 cpe:2.3:a:codesys:hmi:*:*:*:*:*:*:*:*
codesys remote_target_visu_toolkit < 3.5.17.10 cpe:2.3:a:codesys:remote_target_visu_toolkit:*:*:*:*:*:*:*:*

References for CVE-2021-36763

cvelogic Threat Intelligence