CVE-2025-13434: A weakness has been identified in jameschz Hush Framework 2.0

This week

MEDIUM 5.3REMOTEDOWNGRADE

CVE-2025-13434 is a medium-severity flaw (CVSS 5.3) affecting hush. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

A weakness has been identified in jameschz Hush Framework 2.0. The impacted element is an unknown function of the file Hush\hush-lib\hush\Util.php of the component HTTP Host Header Handler. This manipulation of the argument $_SERVER['HOST'] causes improper neutralization of http headers for scripting syntax. The attack is possible to be carried out remotely. The exploit has been made available to the public and could be exploited. The vendor was

Why this priority

Public exploit reference
Remotely exploitable, no login, no user action

No fix is published yet: follow the downgrade or mitigation steps.

Risk facts

CVSS score	5.3 (Medium)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	0.5% (top 57%)
CISA exploited list	No
Weakness	CWE-644
Published	2025-11-20
Last modified	2026-10-18

Publisher (CNA): VulDB · Vendor: jameschz

Last updated 2026-10-18 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2025-11-20 15:17 UTCPublished CVE record published
2026-10-18 20:10 UTCUpdated Record last modified

jameschz hush DOWNGRADE

Affected: 2.0

Fixed in: no fixed release known

Safe to downgrade to: a release before 2.0

1. Check installed version

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

2. No fixed release: DOWNGRADE to a release before 2.0 (Debian / Ubuntu)

apt-cache madison hush sudo apt install hush=<VERSION_BEFORE_2.0> sudo apt-mark hold hush

2. No fixed release: DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list hush sudo dnf downgrade hush-<VERSION_BEFORE_2.0> sudo dnf versionlock add hush

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-2025-13434?

hush: downgrade or apply the listed mitigation. Exact commands for each OS are on this page.

Is CVE-2025-13434 being exploited?

CVE-2025-13434 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-2025-13434 affect?

CVE-2025-13434 affects hush. Severity is medium (CVSS 5.3). A weakness has been identified in jameschz Hush Framework 2.0. The impacted element is an unknown function of the file Hush\hush-lib\hush\Util.php of the component HTTP Host Header Handler. This manipulation of the argument $_SERVER['HOST']

How urgent is CVE-2025-13434?

Priority 39/100. Public exploit reference; Remotely exploitable, no login, no user action

Software pages

PHP vulnerabilities

References

← Back to latest CVEs