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» CVE-2020-5404
The HttpClient from Reactor Netty, versions 0.9.x prior to 0.9.5, and versions 0.8.x prior to 0.8.16, may be used incorrectly, leading to a credentials leak during a redirect to a different domain. In order for this to happen, the HttpClient must have been explicitly configured to follow redirects.
NVD Status： Modified ，CVE State: published
Threat Intelligence & Risk Assessment for CVE-2020-5404
Conclusion & alert: CVE-2020-5404 is rated Low Risk (39.5/100) : CVSS Medium severity, with low exploitation likelihood (EPSS 0.23%).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-2020-5404
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
2025-12-16
0.28%
0.23%
-0.05%
2
2025-12-15
0.51%
0.28%
-0.23%
3
2025-11-21
—
0.51%
—
Full EPSS history
(12 records total)
Common vulnerability scoring system (CVSS) metrics for CVE-2020-5404
CVSS metrics for this CVE.
Base score
Version
Severity
Vector
Exploitability
Impact
Score source
5.9
3.1
MEDIUM
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:L/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:L)
A normal user session is enough; they don’t have to be admin.
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:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
1.6
4.2
[email protected]
6.5
3.0
MEDIUM
CVSS:3.0/AV:N/AC:H/PR:L/UI:R/S:C/C:H/I:L/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:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
1.3
4.7
[email protected]
4.9
2.0
MEDIUM
AV:N/AC:M/Au:S/C:P/I:P/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:S)
A single authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:N)
No availability impact.
6.8
4.9
[email protected]
Weakness enumeration for CVE-2020-5404
GitHub Security Advisory for CVE-2020-5404
GHSA-gpch-h32j-gx6x · Severity: medium · Ecosystem: maven
— Insufficiently Protected Credentials in Reactor Netty
OS Trackers for CVE-2020-5404
Affected software / configurations for CVE-2020-5404
Vendor
Product
Version
Raw CPE
pivotal
reactor_netty
>= 0.8.0, <= 0.8.15
cpe:2.3:a:pivotal:reactor_netty:*:*:*:*:*:*:*:*
pivotal
reactor_netty
>= 0.9.0, <= 0.9.4
cpe:2.3:a:pivotal:reactor_netty:*:*:*:*:*:*:*:*
References for CVE-2020-5404
cvelogic
Threat Intelligence