CVE-2021-25994: In Userfrosting, versions v0.3.1 to v4.6.2 are vulnerable to Host Header Injection

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HIGH 8.8UPGRADE

CVE-2021-25994 is a high-severity flaw (CVSS 8.8) affecting userfrosting. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

In Userfrosting, versions v0.3.1 to v4.6.2 are vulnerable to Host Header Injection. By luring a victim application user to click on a link, an unauthenticated attacker can use the “forgot password” functionality to reset the victim’s password and successfully take over their account.

Why this priority

High severity
Public exploit reference

A fixed release or distro patch exists.

Risk facts

CVSS score	8.8 (High)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	Required
EPSS exploit chance	1.6% (top 24%)
CISA exploited list	No
Weakness	CWE-74
Published	2022-01-03
Last modified	2026-06-17

Publisher (CNA): Mend · Vendor: userfrosting

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

Am I affected?

Timeline

2022-01-03 07:15 UTCPublished CVE record published
2026-06-17 03:42 UTCUpdated Record last modified

userfrosting userfrosting UPGRADE

Affected: >= 0.3.1 and < 4.6.3

Fixed in: 4.6.3

Safe to downgrade to: a release before 0.3.1

1. Check installed version

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

2. UPGRADE to 4.6.3 (Debian / Ubuntu)

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

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade userfrosting

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 0.3.1 (Debian / Ubuntu)

apt-cache madison userfrosting sudo apt install userfrosting=<VERSION_BEFORE_0.3.1> sudo apt-mark hold userfrosting

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

dnf --showduplicates list userfrosting sudo dnf downgrade userfrosting-<VERSION_BEFORE_0.3.1> sudo dnf versionlock add userfrosting

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-2021-25994?

userfrosting: upgrade to 4.6.3. Exact commands for each OS are on this page.

Is CVE-2021-25994 being exploited?

CVE-2021-25994 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-2021-25994 affect?

CVE-2021-25994 affects userfrosting. Severity is high (CVSS 8.8). In Userfrosting, versions v0.3.1 to v4.6.2 are vulnerable to Host Header Injection. By luring a victim application user to click on a link, an unauthenticated attacker can use the “forgot password” functionality to reset the victim’s passwo

How urgent is CVE-2021-25994?

Priority 55/100. High severity; Public exploit reference

References

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