CVE-2021-27018

The mechanism which performs certificate validation was discovered to have a flaw that resulted in certificates signed by an internal certificate authority to not be properly validated. This issue only affects clients that are configured to utilize Tenable.sc as the vulnerability data source.

Published: 2021-08-30 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-27018 is rated Low Risk (39.2/100): CVSS High severity, with low exploitation likelihood (EPSS 0.07%). 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-2021-27018

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 2023-03-07 0.89% 0.07% -0.81%
2 2022-04-01 4.50% 0.89% -3.61%
3 2022-02-04 — 4.50% —

Full EPSS history (5 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-27018

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:N/I:H/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:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N)
Service keeps running; no real outage angle.
 3.9 3.6 [email protected]
4.3 2.0 MEDIUM
AV:N/AC:M/Au:N/C:N/I:P/A:N 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:N)
No confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:N)
No availability impact.
 8.6 2.9 [email protected]

Weakness enumeration for CVE-2021-27018

OS Trackers for CVE-2021-27018

vendor priority summary link
ubuntu medium CVE-2021-27018 medium priority: Ubuntu including 1 source packages (puppet), 15 status rows across 15 suites (bionic, focal, hirsute, impish, jammy, kinetic, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): DNE 6, needs-triage 6, ignored 3. https://ubuntu.com/security/CVE-2021-27018

Affected software / configurations for CVE-2021-27018

Vendor Product Version Raw CPE
puppet remediate < 2.0.1 cpe:2.3:a:puppet:remediate:*:*:*:*:*:*:*:*

References for CVE-2021-27018

cvelogic Threat Intelligence