CVE-2020-4048 [Medium] | Security Vulnerability in Wordpress

In affected versions of WordPress, due to an issue in wp_validate_redirect() and URL sanitization, an arbitrary external link can be crafted leading to unintended/open redirect when clicked. This has been patched in version 5.4.2, along with all the previously affected versions via a minor release (5.3.4, 5.2.7, 5.1.6, 5.0.10, 4.9.15, 4.8.14, 4.7.18, 4.6.19, 4.5.22, 4.4.23, 4.3.24, 4.2.28, 4.1.31, 4.0.31, 3.9.32, 3.8.34, 3.7.34).

#	Date	Old EPSS score	New EPSS score	Delta (New - Old)
1	2026-06-15	3.50%	2.33%	-1.17%
2	2026-03-04	1.88%	3.50%	+1.62%
3	2026-03-01	—	1.88%	—

Date

Old EPSS score

New EPSS score

Delta (New - Old)

2026-06-15

3.50%

2.33%

-1.17%

2026-03-04

1.88%

3.50%

+1.62%

2026-03-01

—

1.88%

—

Base score	Version	Severity	Vector	Exploitability	Impact	Score source
5.7	3.1	MEDIUM	`CVSS:3.1/AV:N/AC:L/PR:L/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:L) Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup. 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: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.	2.1	3.6	[email protected]
5.7	3.1	MEDIUM	`CVSS:3.1/AV:N/AC:L/PR:L/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:L) Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup. 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: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.	2.1	3.6	[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]

Base score

Version

Severity

Vector

Exploitability

Impact

Score source

5.7

3.1

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:L/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:L): Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
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: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.

2.1

3.6

[email protected]

5.7

3.1

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:L/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:L): Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
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: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.

2.1

3.6

[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]

OS Trackers for CVE-2020-4048

vendor	priority	summary	link
`debian`	not yet assigned	CVE-2020-4048 not yet assigned priority: Debian including 1 source packages (wordpress), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5.	https://security-tracker.debian.org/tracker/CVE-2020-4048
`ubuntu`	medium	CVE-2020-4048 medium priority: Ubuntu including 1 source packages (wordpress), 17 status rows across 17 suites (bionic, eoan, focal, groovy, hirsute, impish, jammy, kinetic, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): not-affected 6, ignored 5, needs-triage 4, DNE 1, released 1.	https://ubuntu.com/security/CVE-2020-4048

Affected software / configurations for CVE-2020-4048

Vendor	Product	Version	Raw CPE
wordpress	wordpress	>= 3.7, < 3.7.34	cpe:2.3:a:wordpress:wordpress::::::::
wordpress	wordpress	>= 3.8, < 3.8.34	cpe:2.3:a:wordpress:wordpress::::::::
wordpress	wordpress	>= 3.9, < 3.9.32	cpe:2.3:a:wordpress:wordpress::::::::
wordpress	wordpress	>= 4.0, < 4.0.31	cpe:2.3:a:wordpress:wordpress::::::::
wordpress	wordpress	>= 4.1, < 4.1.31	cpe:2.3:a:wordpress:wordpress::::::::
wordpress	wordpress	>= 4.2, < 4.2.28	cpe:2.3:a:wordpress:wordpress::::::::
wordpress	wordpress	>= 4.3, < 4.3.24	cpe:2.3:a:wordpress:wordpress::::::::
wordpress	wordpress	>= 4.4, < 4.4.23	cpe:2.3:a:wordpress:wordpress::::::::
wordpress	wordpress	>= 4.5, < 4.5.22	cpe:2.3:a:wordpress:wordpress::::::::
wordpress	wordpress	>= 4.6, < 4.6.19	cpe:2.3:a:wordpress:wordpress::::::::
wordpress	wordpress	>= 4.7, < 4.7.18	cpe:2.3:a:wordpress:wordpress::::::::
wordpress	wordpress	>= 4.8, < 4.8.14	cpe:2.3:a:wordpress:wordpress::::::::
wordpress	wordpress	>= 4.9, < 4.9.15	cpe:2.3:a:wordpress:wordpress::::::::
wordpress	wordpress	>= 5.0, < 5.0.10	cpe:2.3:a:wordpress:wordpress::::::::
wordpress	wordpress	>= 5.1, < 5.1.6	cpe:2.3:a:wordpress:wordpress::::::::
wordpress	wordpress	>= 5.2, < 5.2.7	cpe:2.3:a:wordpress:wordpress::::::::
wordpress	wordpress	>= 5.3.0, < 5.3.4	cpe:2.3:a:wordpress:wordpress::::::::
wordpress	wordpress	>= 5.4, < 5.4.2	cpe:2.3:a:wordpress:wordpress::::::::
fedoraproject	fedora	32	cpe:2.3:o:fedoraproject:fedora:32:::::::*
fedoraproject	fedora	33	cpe:2.3:o:fedoraproject:fedora:33:::::::*
debian	debian_linux	8.0	cpe:2.3:o:debian:debian_linux:8.0:::::::*
debian	debian_linux	9.0	cpe:2.3:o:debian:debian_linux:9.0:::::::*
debian	debian_linux	10.0	cpe:2.3:o:debian:debian_linux:10.0:::::::*

References for CVE-2020-4048

URL	Tags
https://github.com/WordPress/wordpress-develop/commit/6ef777e9a022bee2a80fa671118e7e2657e52693	Patch
https://github.com/WordPress/wordpress-develop/security/advisories/GHSA-q6pw-gvf4-5fj5	Third Party Advisory
https://lists.debian.org/debian-lts-announce/2020/07/msg00000.html	Mailing List Third Party Advisory
https://lists.debian.org/debian-lts-announce/2020/09/msg00011.html	Mailing List Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/773N2ZV7QEMBGKH6FBKI6Q5S3YJMW357/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ODNHXVJS25YVWYQHOCICXTLIN5UYJFDN/
https://wordpress.org/news/2020/06/wordpress-5-4-2-security-and-maintenance-release/	Release Notes Vendor Advisory
https://www.debian.org/security/2020/dsa-4709	Mailing List Third Party Advisory

URL

CVE-2020-4048 | Open redirect in wp_validate_redirect() in WordPress

Exploit prediction scoring system (EPSS) score for CVE-2020-4048

Common vulnerability scoring system (CVSS) metrics for CVE-2020-4048

Weakness enumeration for CVE-2020-4048

OS Trackers for CVE-2020-4048

Affected software / configurations for CVE-2020-4048

References for CVE-2020-4048