CVE-2018-8753

The IKEv1 implementation in Clavister cOS Core before 11.00.11, 11.20.xx before 11.20.06, and 12.00.xx before 12.00.09 allows remote attackers to decrypt RSA-encrypted nonces by leveraging a Bleichenbacher attack.

Published: 2018-08-15 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2018-8753 is rated Moderate Risk (42.1/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 0.30%). 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-2018-8753

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 2026-04-05 0.35% 0.30% -0.06%
2 2026-03-03 0.34% 0.35% +0.01%
3 2026-03-01 — 0.34% —

Full EPSS history (11 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2018-8753

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.9 3.0 MEDIUM
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/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: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:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
 2.2 3.6 [email protected]
4.3 2.0 MEDIUM
AV:N/AC:M/Au:N/C:P/I:N/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:P)
Partial confidentiality impact.
Integrity impact (I:N)
No integrity impact.
Availability impact (A:N)
No availability impact.
 8.6 2.9 [email protected]

Weakness enumeration for CVE-2018-8753

Affected software / configurations for CVE-2018-8753

Vendor Product Version Raw CPE
clavister cos_core < 11.00.11 cpe:2.3:a:clavister:cos_core:*:*:*:*:*:*:*:*
clavister cos_core >= 11.20.00, < 11.20.06 cpe:2.3:a:clavister:cos_core:*:*:*:*:*:*:*:*
clavister cos_core >= 12.00.00, < 12.00.09 cpe:2.3:a:clavister:cos_core:*:*:*:*:*:*:*:*

References for CVE-2018-8753

cvelogic Threat Intelligence