How severe is CVE-2021-25033?

CVE-2021-25033 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2021-25033 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (84th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-25033?

CVE-2021-25033 affects Noptin. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-25033?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-25033 published?

CVE-2021-25033 was published on 2022-02-14 and last updated on 2026-06-17.

CVE-2021-25033

CVE-2021-25033 is a medium-severity vulnerability in Noptin with a CVSS 3.x base score of 6.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-601.

Key facts

Severity: Medium (CVSS 3.x base score 6.1)
CVSS v2: 5.8
EPSS exploit prediction: 3% (84th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-601
Affected product: Noptin
Published: 2022-02-14
Last modified: 2026-06-17

Description

The WordPress Newsletter Plugin WordPress plugin before 1.6.5 does not validate the to parameter before redirecting the user to its given value, leading to an open redirect issue

Frequently asked questions

What is CVE-2021-25033?: The WordPress Newsletter Plugin WordPress plugin before 1.6.5 does not validate the to parameter before redirecting the user to its given value, leading to an open redirect issue
How severe is CVE-2021-25033?: CVE-2021-25033 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2021-25033 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (84th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-25033?: CVE-2021-25033 affects Noptin. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-25033?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-25033 published?: CVE-2021-25033 was published on 2022-02-14 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:noptin:noptin:*:*:*:*:*:wordpress:*:*

More vulnerabilities in Noptin

CVE-2022-46803 — Medium (CVSS 6.1): Improper Neutralization of Formula Elements in a CSV File vulnerability in Noptin Newsletter Simple Newsletter Plugin…

All CVEs affecting Noptin →

Other CWE-601 (Open Redirect) vulnerabilities

CVE-2018-3774 — Critical (CVSS 10.0): Incorrect parsing in url-parse <1.4.3 returns wrong hostname which leads to multiple vulnerabilities such as SSRF, Open…
CVE-2019-25282 — Critical (CVSS 9.8): V-SOL GPON/EPON OLT Platform v2.03 contains an open redirect vulnerability in the script that allows attackers to…
CVE-2020-36912 — Critical (CVSS 9.8): Plexus anblick Digital Signage Management 3.1.13 contains an open redirect vulnerability in the 'PantallaLogin' script…
CVE-2025-43526 — Critical (CVSS 9.8): This issue was addressed with improved URL validation. This issue is fixed in Safari 26.2, macOS Tahoe 26.2. On a Mac…
CVE-2025-55031 — Critical (CVSS 9.8): Malicious pages could use Firefox for iOS to pass FIDO: links to the OS and trigger the hybrid passkey transport. An…
CVE-2024-22891 — Critical (CVSS 9.8): Nteract v.0.28.0 was discovered to contain a remote code execution (RCE) vulnerability via the Markdown link.

Browse all CWE-601 (Open Redirect) vulnerabilities →