CVE-2020-15078

OpenVPN 2.5.1 and earlier versions allows a remote attackers to bypass authentication and access control channel data on servers configured with deferred authentication, which can be used to potentially trigger further information leaks.

Published: 2021-04-26 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2020-15078 is rated High Risk (66.6/100): CVSS High severity, with high exploitation likelihood (EPSS 5.11%, 91th percentile). EPSS ranks this CVE among the most likely to be exploited in the near term. EPSS rose +4.61% 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-2020-15078

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 2026-06-15 0.49% 5.11% +4.61%
2 2026-05-22 0.30% 0.49% +0.19%
3 2025-11-21 — 0.30% —

Full EPSS history (27 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2020-15078

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: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: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: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.
 3.9 3.6 [email protected]
5.0 2.0 MEDIUM
AV:N/AC:L/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:L)
Exploitation conditions are straightforward and predictable.
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.
 10.0 2.9 [email protected]

Weakness enumeration for CVE-2020-15078

OS Trackers for CVE-2020-15078

vendor priority summary link
alpine high CVE-2020-15078: 1 source package rows (openvpn); 20 state rows across 10 repos (3.10-main, 3.11-main, 3.12-main, 3.17-main, 3.18-main, 3.19-main, 3.20-main, 3.21-main, 3.22-main, edge-main); fixed 10, open 10. https://security.alpinelinux.org/vuln/CVE-2020-15078
debian not yet assigned CVE-2020-15078 not yet assigned priority: Debian including 1 source packages (openvpn), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2020-15078
gentoo normal CVE-2020-15078: 1 GLSA(s) (202105-25), 1 atom(s) (net-vpn/openvpn); latest impact normal. https://bugs.gentoo.org/buglist.cgi?quicksearch=CVE-2020-15078
suse medium CVE-2020-15078 severity moderate: SUSE including 36 source package names (openvpn, openvpn-2.0.9-143.47.6.1, …), 49 product×package rows across 19 product lines (SUSE Linux Enterprise Module for Basesystem 15 SP2, SUSE Linux Enterprise Module for Basesystem 15 SP3, … (19 product lines)): Fixed 46, Known Not Affected 3. https://www.suse.com/security/cve/CVE-2020-15078/
ubuntu medium CVE-2020-15078 medium priority: Ubuntu including 1 source packages (openvpn), 9 status rows across 9 suites (bionic, focal, groovy, hirsute, impish, jammy, trusty, upstream, xenial): released 7, not-affected 2. https://ubuntu.com/security/CVE-2020-15078

Affected software / configurations for CVE-2020-15078

Vendor Product Version Raw CPE
openvpn openvpn < 2.4.11 cpe:2.3:a:openvpn:openvpn:*:*:*:*:*:*:*:*
openvpn openvpn >= 2.5.0, < 2.5.2 cpe:2.3:a:openvpn:openvpn:*:*:*:*:*:*:*:*
fedoraproject fedora 32 cpe:2.3:o:fedoraproject:fedora:32:*:*:*:*:*:*:*
fedoraproject fedora 33 cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*
fedoraproject fedora 34 cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*
canonical ubuntu_linux 18.04 cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:*
canonical ubuntu_linux 20.04 cpe:2.3:o:canonical:ubuntu_linux:20.04:*:*:*:lts:*:*:*
canonical ubuntu_linux 20.10 cpe:2.3:o:canonical:ubuntu_linux:20.10:*:*:*:*:*:*:*
canonical ubuntu_linux 21.04 cpe:2.3:o:canonical:ubuntu_linux:21.04:*:*:*:*:*:*:*
debian debian_linux 9.0 cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*

References for CVE-2020-15078

cvelogic Threat Intelligence