CVE-2017-12373

A vulnerability in the TLS protocol implementation of legacy Cisco ASA 5500 Series (ASA 5505, 5510, 5520, 5540, and 5550) devices could allow an unauthenticated, remote attacker to access sensitive information, aka a Return of Bleichenbacher's Oracle Threat (ROBOT) attack. An attacker could iteratively query a server running a vulnerable TLS stack implementation to perform cryptanalytic operations that may allow decryption of previously captured TLS sessions. Cisco Bug IDs: CSCvg97652.

Published: 2017-12-15 Last update: 2026-05-13 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2017-12373 is rated Moderate Risk (63.1/100): CVSS Medium severity, with high exploitation likelihood (EPSS 66.94%, 99th percentile). EPSS ranks this CVE among the most likely to be exploited in the near term. EPSS rose +5.33% over the last day, indicating growing attacker interest. High exploitation likelihood—assess exposure and prioritize 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-2017-12373

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 2026-03-17 61.62% 66.94% +5.33%
2 2025-11-12 61.96% 61.62% -0.34%
3 2025-07-01 — 61.96% —

Full EPSS history (12 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2017-12373

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-2017-12373

Affected software / configurations for CVE-2017-12373

Vendor Product Version Raw CPE
cisco adaptive_security_appliance_5505_firmware — cpe:2.3:o:cisco:adaptive_security_appliance_5505_firmware:-:*:*:*:*:*:*:*
cisco adaptive_security_appliance_5510_firmware — cpe:2.3:o:cisco:adaptive_security_appliance_5510_firmware:-:*:*:*:*:*:*:*
cisco adaptive_security_appliance_5520_firmware — cpe:2.3:o:cisco:adaptive_security_appliance_5520_firmware:-:*:*:*:*:*:*:*
cisco adaptive_security_appliance_5540_firmware — cpe:2.3:o:cisco:adaptive_security_appliance_5540_firmware:-:*:*:*:*:*:*:*
cisco adaptive_security_appliance_5550_firmware — cpe:2.3:o:cisco:adaptive_security_appliance_5550_firmware:-:*:*:*:*:*:*:*

References for CVE-2017-12373

cvelogic Threat Intelligence