CVE-2020-4027

Affected versions of Atlassian Confluence Server and Data Center allowed remote attackers with system administration permissions to bypass velocity template injection mitigations via an injection vulnerability in custom user macros. The affected versions are before version 7.4.5, and from version 7.5.0 before 7.5.1.

Published: 2020-07-01 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2020-4027 is rated Low Risk (31.4/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.15%). Mandatory action: 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-2020-4027

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 2025-12-22 0.15% 0.15% -0.00%
2 2025-03-17 0.10% 0.15% +0.05%
3 2023-03-07 0.10%

Full EPSS history (7 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2020-4027

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
4.7 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:L 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:H)
They need powerful rights—admin, root, or similar—before this pays off.
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:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:L)
Might cause slowdowns, glitches, or partial disruption—not a full brick.
1.2 3.4 [email protected]
6.5 2.0 MEDIUM
AV:N/AC:L/Au:S/C:P/I:P/A:P 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:S)
A single authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
8.0 6.4 [email protected]

Weakness enumeration for CVE-2020-4027

Affected software / configurations for CVE-2020-4027

Vendor Product Version Raw CPE
atlassian confluence < 7.4.5 cpe:2.3:a:atlassian:confluence:*:*:*:*:*:*:*:*
atlassian confluence_server >= 7.5.0, < 7.5.1 cpe:2.3:a:atlassian:confluence_server:*:*:*:*:*:*:*:*

References for CVE-2020-4027

URL Tags
https://jira.atlassian.com/browse/CONFSERVER-59898 Issue Tracking Patch Release Notes Vendor Advisory
cvelogic Threat Intelligence