CVE-2021-41987

Exp

In the SCEP Server of RouterOS in certain Mikrotik products, an attacker can trigger a heap-based buffer overflow that leads to remote code execution. The attacker must know the scep_server_name value. This affects RouterOS 6.46.8, 6.47.9, and 6.47.10.

Published: 2022-03-16 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-41987 is rated High Exploit Risk (81/100): CVSS High severity, with high exploitation likelihood (EPSS 48.98%, 98th percentile). 1 public exploit reference(s) are indexed (Exploit-DB). Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

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

Public exploit references (Exploit-DB) for CVE-2021-41987

EDB-ID Source Kind Published Link
— nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2021-41987

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 2026-05-23 49.62% 48.98% -0.65%
2 2025-12-28 45.85% 49.62% +3.77%
3 2025-12-27 — 45.85% —

Full EPSS history (30 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-41987

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
8.1 3.1 HIGH
CVSS:3.1/AV:N/AC:H/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:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
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.
 2.2 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-2021-41987

Affected software / configurations for CVE-2021-41987

Vendor Product Version Raw CPE
mikrotik routeros 6.46.8 cpe:2.3:o:mikrotik:routeros:6.46.8:*:*:*:*:*:*:*
mikrotik routeros 6.47.9 cpe:2.3:o:mikrotik:routeros:6.47.9:*:*:*:*:*:*:*
mikrotik routeros 6.47.10 cpe:2.3:o:mikrotik:routeros:6.47.10:*:*:*:*:*:*:*

References for CVE-2021-41987

URL Tags
https://mikrotik.com/download/archive Release Notes Vendor Advisory
https://teamt5.org/en/posts/vulnerability-mikrotik-cve-2021-41987/ Exploit Third Party Advisory
cvelogic Threat Intelligence