CVE-2023-0567

password_verify() always returns true for some invalid hashes

In PHP 8.0.X before 8.0.28, 8.1.X before 8.1.16 and 8.2.X before 8.2.3, password_verify() function may accept some invalid Blowfish hashes as valid. If such invalid hash ever ends up in the password database, it may lead to an application allowing any password for this entry as valid.

Affected

PHP Group · PHP

CVSS v3.1 NVD

6.2 MEDIUMCVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

CVSS v3.1 CNA

8.1 HIGHCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

CVSS v3.1 PHP

7.7 HIGHCVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

EPSS

0.95% chance of exploitation in the next 30 days, 61st percentile

Published

2023-02-16

Updated

2026-07-19

Proof-of-concept exploits (1)

• php/php-src/security/advisories/GHSA-7fj2-8x79-rjf4

Security advisories

• https://bugs.php.net/bug.php?id=81744

References

• CVE Record
• NVD entry