CVE-2021-40363

A vulnerability has been identified in SIMATIC PCS 7 V8.2 (All versions), SIMATIC PCS 7 V9.0 (All versions), SIMATIC PCS 7 V9.1 (All versions < V9.1 SP1), SIMATIC WinCC V15 and earlier (All versions < V15 SP1 Update 7), SIMATIC WinCC V16 (All versions < V16 Update 5), SIMATIC WinCC V17 (All versions < V17 Update 2), SIMATIC WinCC V17 (All versions <= V17 Update 4), SIMATIC WinCC V7.4 (All versions < V7.4 SP1 Update 19), SIMATIC WinCC V7.5 (All versions < V7.5 SP2 Update 6). The affected component stores the credentials of a local system account in a potentially publicly accessible project file using an outdated cipher algorithm. An attacker may use this to brute force the credentials and take over the system.

Published: 2022-02-09 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-40363 is rated Low Risk (33.2/100): CVSS High severity, with low exploitation likelihood (EPSS 0.16%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

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-2021-40363

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 0.03% 0.16% +0.13%
2 2025-04-20 0.05% 0.03% -0.03%
3 2025-03-24 — 0.05% —

Full EPSS history (5 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-40363

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.8 3.1 HIGH
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
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:L)
A normal user session is enough; they don’t have to be admin.
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:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 1.8 5.9 [email protected]
2.1 2.0 LOW
AV:L/AC:L/Au:N/C:P/I:N/A:N Click to expand
Access vector (AV:L)
Requires local access to the target system.
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.
 3.9 2.9 [email protected]

Weakness enumeration for CVE-2021-40363

Affected software / configurations for CVE-2021-40363

Vendor Product Version Raw CPE
siemens simatic_pcs_7 <= 8.2 cpe:2.3:a:siemens:simatic_pcs_7:*:*:*:*:*:*:*:*
siemens simatic_pcs_7 9.0 cpe:2.3:a:siemens:simatic_pcs_7:9.0:-:*:*:*:*:*:*
siemens simatic_pcs_7 9.1 cpe:2.3:a:siemens:simatic_pcs_7:9.1:-:*:*:*:*:*:*
siemens simatic_wincc < 7.4 cpe:2.3:a:siemens:simatic_wincc:*:*:*:*:*:*:*:*
siemens simatic_wincc 7.4 cpe:2.3:a:siemens:simatic_wincc:7.4:-:*:*:*:*:*:*
siemens simatic_wincc 7.4 cpe:2.3:a:siemens:simatic_wincc:7.4:sp1:*:*:*:*:*:*
siemens simatic_wincc 7.4 cpe:2.3:a:siemens:simatic_wincc:7.4:sp1_update1:*:*:*:*:*:*
siemens simatic_wincc 7.4 cpe:2.3:a:siemens:simatic_wincc:7.4:sp1_update10:*:*:*:*:*:*
siemens simatic_wincc 7.4 cpe:2.3:a:siemens:simatic_wincc:7.4:sp1_update11:*:*:*:*:*:*
siemens simatic_wincc 7.4 cpe:2.3:a:siemens:simatic_wincc:7.4:sp1_update12:*:*:*:*:*:*
siemens simatic_wincc 7.4 cpe:2.3:a:siemens:simatic_wincc:7.4:sp1_update13:*:*:*:*:*:*
siemens simatic_wincc 7.4 cpe:2.3:a:siemens:simatic_wincc:7.4:sp1_update14:*:*:*:*:*:*
siemens simatic_wincc 7.4 cpe:2.3:a:siemens:simatic_wincc:7.4:sp1_update15:*:*:*:*:*:*
siemens simatic_wincc 7.4 cpe:2.3:a:siemens:simatic_wincc:7.4:sp1_update16:*:*:*:*:*:*
siemens simatic_wincc 7.4 cpe:2.3:a:siemens:simatic_wincc:7.4:sp1_update17:*:*:*:*:*:*
siemens simatic_wincc 7.4 cpe:2.3:a:siemens:simatic_wincc:7.4:sp1_update18:*:*:*:*:*:*
siemens simatic_wincc 7.4 cpe:2.3:a:siemens:simatic_wincc:7.4:sp1_update2:*:*:*:*:*:*
siemens simatic_wincc 7.4 cpe:2.3:a:siemens:simatic_wincc:7.4:sp1_update3:*:*:*:*:*:*
siemens simatic_wincc 7.4 cpe:2.3:a:siemens:simatic_wincc:7.4:sp1_update4:*:*:*:*:*:*
siemens simatic_wincc 7.4 cpe:2.3:a:siemens:simatic_wincc:7.4:sp1_update5:*:*:*:*:*:*
siemens simatic_wincc 7.4 cpe:2.3:a:siemens:simatic_wincc:7.4:sp1_update6:*:*:*:*:*:*
siemens simatic_wincc 7.4 cpe:2.3:a:siemens:simatic_wincc:7.4:sp1_update7:*:*:*:*:*:*
siemens simatic_wincc 7.4 cpe:2.3:a:siemens:simatic_wincc:7.4:sp1_update8:*:*:*:*:*:*
siemens simatic_wincc 7.4 cpe:2.3:a:siemens:simatic_wincc:7.4:sp1_update9:*:*:*:*:*:*
siemens simatic_wincc 7.4 cpe:2.3:a:siemens:simatic_wincc:7.4:update_1:*:*:*:*:*:*
siemens simatic_wincc 7.5 cpe:2.3:a:siemens:simatic_wincc:7.5:-:*:*:*:*:*:*
siemens simatic_wincc 7.5 cpe:2.3:a:siemens:simatic_wincc:7.5:sp1:*:*:*:*:*:*
siemens simatic_wincc 7.5 cpe:2.3:a:siemens:simatic_wincc:7.5:sp1_update1:*:*:*:*:*:*
siemens simatic_wincc 7.5 cpe:2.3:a:siemens:simatic_wincc:7.5:sp1_update2:*:*:*:*:*:*
siemens simatic_wincc 7.5 cpe:2.3:a:siemens:simatic_wincc:7.5:sp2:*:*:*:*:*:*
siemens simatic_wincc 7.5 cpe:2.3:a:siemens:simatic_wincc:7.5:sp2_update1:*:*:*:*:*:*
siemens simatic_wincc 7.5 cpe:2.3:a:siemens:simatic_wincc:7.5:sp2_update2:*:*:*:*:*:*
siemens simatic_wincc 7.5 cpe:2.3:a:siemens:simatic_wincc:7.5:sp2_update3:*:*:*:*:*:*
siemens simatic_wincc 7.5 cpe:2.3:a:siemens:simatic_wincc:7.5:sp2_update4:*:*:*:*:*:*
siemens simatic_wincc 7.5 cpe:2.3:a:siemens:simatic_wincc:7.5:sp2_update5:*:*:*:*:*:*
siemens simatic_wincc 13 cpe:2.3:a:siemens:simatic_wincc:13:-:*:*:*:*:*:*
siemens simatic_wincc 13 cpe:2.3:a:siemens:simatic_wincc:13:sp1:*:*:*:*:*:*
siemens simatic_wincc 13 cpe:2.3:a:siemens:simatic_wincc:13:sp2:*:*:*:*:*:*
siemens simatic_wincc 14.0.1 cpe:2.3:a:siemens:simatic_wincc:14.0.1:*:*:*:*:*:*:*
siemens simatic_wincc 15 cpe:2.3:a:siemens:simatic_wincc:15:*:*:*:*:*:*:*
siemens simatic_wincc 15.1 cpe:2.3:a:siemens:simatic_wincc:15.1:-:*:*:*:*:*:*
siemens simatic_wincc 15.1 cpe:2.3:a:siemens:simatic_wincc:15.1:update_1:*:*:*:*:*:*
siemens simatic_wincc 15.1 cpe:2.3:a:siemens:simatic_wincc:15.1:update_2:*:*:*:*:*:*
siemens simatic_wincc 15.1 cpe:2.3:a:siemens:simatic_wincc:15.1:update_3:*:*:*:*:*:*
siemens simatic_wincc 15.1 cpe:2.3:a:siemens:simatic_wincc:15.1:update_4:*:*:*:*:*:*
siemens simatic_wincc 15.1 cpe:2.3:a:siemens:simatic_wincc:15.1:update_5:*:*:*:*:*:*
siemens simatic_wincc 15.1 cpe:2.3:a:siemens:simatic_wincc:15.1:update_6:*:*:*:*:*:*
siemens simatic_wincc 16 cpe:2.3:a:siemens:simatic_wincc:16:-:*:*:*:*:*:*
siemens simatic_wincc 16 cpe:2.3:a:siemens:simatic_wincc:16:update1:*:*:*:*:*:*
siemens simatic_wincc 16 cpe:2.3:a:siemens:simatic_wincc:16:update2:*:*:*:*:*:*
siemens simatic_wincc 16 cpe:2.3:a:siemens:simatic_wincc:16:update3:*:*:*:*:*:*
siemens simatic_wincc 16 cpe:2.3:a:siemens:simatic_wincc:16:update4:*:*:*:*:*:*
siemens simatic_wincc 17 cpe:2.3:a:siemens:simatic_wincc:17:-:*:*:*:*:*:*
siemens simatic_wincc 17 cpe:2.3:a:siemens:simatic_wincc:17:update1:*:*:*:*:*:*

References for CVE-2021-40363

cvelogic Threat Intelligence