CVE-2024-3096 — In PHP version 8

In PHP version 8.1.* before 8.1.28, 8.2.* before 8.2.18, 8.3.* before 8.3.5, if a password stored with password_hash() starts with a null byte (\x00), testing a blank string as the password via password_verify() will incorrectly return true.

01What is this vulnerability?

In PHP version 8.1.* before 8.1.28, 8.2.* before 8.2.18, 8.3.* before 8.3.5, if a password stored with password_hash() starts with a null byte (\x00), testing a blank string as the password via password_verify() will incorrectly return true.

02Affected products

Vendor	Product	Versions
PHP Group	PHP	8.1.*, 8.2.*, 8.3.*

03Active exploitation status

Not currently listed on the CISA Known Exploited Vulnerabilities (KEV) catalog. EPSS is the best forward-looking signal — see the EPSS row above.

04Recommended remediation

• Patch to a fixed version listed in the vendor advisory (see references below).
• Mitigate with WAF rules, network egress filters, or feature flags where the patch is not yet available.
• Hunt historical logs for exploitation indicators — see Detection signatures below.

05Technical details

For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.

06Detection signatures

Open the Sigma generator with a pre-filled prompt for this CVE to draft a starting detection in your stack of choice:

Open in Sigma generator →

07Related CVEs

No directly-cited follow-up CVEs in the KB record for this advisory. The references list in section 09 carries the vendor cross-references.

08Timeline

• Published: 2024-04-29T03:42:04.093Z
• Last modified: 2025-11-04T17:19:57.320Z

09References

• github.com — https://github.com/php/php-src/security/advisories/GHSA-h746-cjrr-wfmr
• www.openwall.com — http://www.openwall.com/lists/oss-security/2024/04/12/11
• lists.debian.org — https://lists.debian.org/debian-lts-announce/2024/05/msg00005.html
• security.netapp.com — https://security.netapp.com/advisory/ntap-20240510-0010/