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» CVE-2021-43556
FATEK WinProladder Versions 3.30_24518 and prior are vulnerable to a stack-based buffer overflow while processing project files, which may allow an attacker to execute arbitrary code.
NVD Status： Modified ，CVE State: published
Threat Intelligence & Risk Assessment for CVE-2021-43556
Conclusion & alert: CVE-2021-43556 is rated Moderate Risk (60.4/100) : CVSS High severity, with medium exploitation likelihood (EPSS 2.09%).Core evidence: EPSS rose +1.51% over the last day, indicating growing attacker interest.Mandatory action: 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-2021-43556
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
0.58%
2.09%
+1.51%
2
2025-04-10
0.39%
0.58%
+0.19%
3
2025-04-07
—
0.39%
—
Full EPSS history
(15 records total)
Common vulnerability scoring system (CVSS) metrics for CVE-2021-43556
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:N/UI:R/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:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
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]
7.8
3.1
HIGH
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/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:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
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]
6.8
2.0
MEDIUM
AV:N/AC:M/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:M)
Exploitation needs some favorable conditions, but not exceptional ones.
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.
8.6
6.4
[email protected]
Weakness enumeration for CVE-2021-43556
Affected software / configurations for CVE-2021-43556
Vendor
Product
Version
Raw CPE
fatek
winproladder
<= 3.30_24518
cpe:2.3:a:fatek:winproladder:*:*:*:*:*:*:*:*
References for CVE-2021-43556
cvelogic
Threat Intelligence