CVE-2021-40358

A vulnerability has been identified in SIMATIC PCS 7 V8.2 (All versions), SIMATIC PCS 7 V9.0 (All versions < V9.0 SP3 UC04), 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 V7.4 (All versions < V7.4 SP1 Update 19), SIMATIC WinCC V7.5 (All versions < V7.5 SP2 Update 5). Legitimate file operations on the web server of the affected systems do not properly neutralize special elements within the pathname. An attacker could then cause the pathname to resolve to a location outside of the restricted directory on the server and read, write or delete unexpected critical files.

Published: 2021-11-09 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-40358 is rated Moderate Risk (62.9/100): CVSS Critical severity, with medium exploitation likelihood (EPSS 1.23%). 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-2021-40358

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 0.69% 1.23% +0.54%
2 2025-10-20 0.58% 0.69% +0.12%
3 2025-03-30 — 0.58% —

Full EPSS history (12 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-40358

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
9.9 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H 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: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:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
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.
 3.1 6.0 [email protected]
9.8 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H 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: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.
 3.9 5.9 [email protected]
7.5 2.0 HIGH
AV:N/AC:L/Au:N/C:P/I:P/A:P 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:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
 10.0 6.4 [email protected]

Weakness enumeration for CVE-2021-40358

Affected software / configurations for CVE-2021-40358

Vendor Product Version Raw CPE
siemens simatic_pcs_7 8.2 cpe:2.3:a:siemens:simatic_pcs_7:8.2:*:*:*:*:*:*:*
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:7.4:*:*:*:*:*:*:*
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 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: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-2021-40358

cvelogic Threat Intelligence