CVE-2024-8850: The MC4WP: Mailchimp for WordPress plugin for WordPress is vulnerable to Reflected Cross-Site Scripting via th

Routine

MEDIUM 6.1UPGRADE

CVE-2024-8850 is a medium-severity flaw (CVSS 6.1) affecting mailchimp. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

The MC4WP: Mailchimp for WordPress plugin for WordPress is vulnerable to Reflected Cross-Site Scripting via the 'email' parameter when a placeholder such as {email} is used for the field in versions 4.9.9 to 4.9.16 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that execute if they can successfully trick a user into performing an action such

Why this priority

No elevated risk signals yet

A fixed release or distro patch exists.

Risk facts

CVSS score	6.1 (Medium)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	Required
EPSS exploit chance	0.5% (top 59%)
CISA exploited list	No
Weakness	CWE-79
Published	2024-09-19
Last modified	2026-06-17

Publisher (CNA): Wordfence · Vendor: ibericode

Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2024-09-19 04:15 UTCPublished CVE record published
2026-06-17 08:23 UTCUpdated Record last modified

ibericode mailchimp UPGRADE

Affected: >= 4.9.9 and <= 4.9.16

Fixed in: newer than 4.9.16

Safe to downgrade to: a release before 4.9.9

1. Check installed version

apt-cache policy mailchimp || rpm -q mailchimp || mailchimp --version

2. UPGRADE to newer than 4.9.16 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade mailchimp

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade mailchimp

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

3. If no update is available yet, DOWNGRADE to a release before 4.9.9 (Debian / Ubuntu)

apt-cache madison mailchimp sudo apt install mailchimp=<VERSION_BEFORE_4.9.9> sudo apt-mark hold mailchimp

3. If no update is available yet, DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list mailchimp sudo dnf downgrade mailchimp-<VERSION_BEFORE_4.9.9> sudo dnf versionlock add mailchimp

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2024-8850?

mailchimp: upgrade to newer than 4.9.16. Exact commands for each OS are on this page.

Is CVE-2024-8850 being exploited?

CVE-2024-8850 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2024-8850 affect?

CVE-2024-8850 affects mailchimp. Severity is medium (CVSS 6.1). The MC4WP: Mailchimp for WordPress plugin for WordPress is vulnerable to Reflected Cross-Site Scripting via the 'email' parameter when a placeholder such as {email} is used for the field in versions 4.9.9 to 4.9.16 due to insufficient input

How urgent is CVE-2024-8850?

Priority 32/100. No elevated risk signals yet.

Software pages

WordPress vulnerabilities

Related CVEs

CVE-2024-8680 MEDIUM 4.4 UPGRADE The MC4WP: Mailchimp for WordPress plugin for WordPress is vulnerable to Stored Cross-Site Scripting via admin
CVE-2023-51682 MEDIUM 5.3 UPGRADE Missing Authorization vulnerability in ibericode MC4WP.This issue affects MC4WP: from n/a through 4.9.9.

References

← Back to latest CVEs