CVE-2017-8301

LibreSSL 2.5.1 to 2.5.3 lacks TLS certificate verification if SSL_get_verify_result is relied upon for a later check of a verification result, in a use case where a user-provided verification callback returns 1, as demonstrated by acceptance of invalid certificates by nginx.

Published: 2017-04-27 Last update: 2026-05-13 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2017-8301 is rated Moderate Risk (43.4/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 0.43%). 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-2017-8301

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 2026-05-30 0.21% 0.43% +0.23%
2 2025-11-21 0.48% 0.21% -0.27%
3 2025-11-18 — 0.48% —

Full EPSS history (5 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2017-8301

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.3 3.0 MEDIUM
CVSS:3.0/AV:N/AC:H/PR:N/UI:R/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: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: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: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.
 1.6 3.6 [email protected]
2.6 2.0 LOW
AV:N/AC:H/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:H)
Exploitation requires uncommon or highly specific conditions.
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.
 4.9 2.9 [email protected]

Weakness enumeration for CVE-2017-8301

OS Trackers for CVE-2017-8301

vendor priority summary link
alpine — CVE-2017-8301: 1 source package rows (libressl); 10 state rows across 10 repos (3.10-main, 3.11-main, 3.12-main, 3.17-community, 3.18-community, 3.19-community, 3.20-community, 3.21-community, 3.22-community, edge-community); fixed 10, open 0. https://security.alpinelinux.org/vuln/CVE-2017-8301

Affected software / configurations for CVE-2017-8301

Vendor Product Version Raw CPE
openbsd libressl 2.5.1 cpe:2.3:a:openbsd:libressl:2.5.1:*:*:*:*:*:*:*
openbsd libressl 2.5.2 cpe:2.3:a:openbsd:libressl:2.5.2:*:*:*:*:*:*:*
openbsd libressl 2.5.3 cpe:2.3:a:openbsd:libressl:2.5.3:*:*:*:*:*:*:*

References for CVE-2017-8301

URL Tags
http://seclists.org/oss-sec/2017/q2/145 Mailing List Third Party Advisory
http://www.securityfocus.com/bid/98076 Third Party Advisory VDB Entry
https://github.com/libressl-portable/portable/issues/307 Issue Tracking Patch Third Party Advisory
https://trac.nginx.org/nginx/ticket/1257 Issue Tracking Patch Third Party Advisory
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