CVE-2024-3096: PHP function password_verify can erroneously return true when argument contains NUL

Published Apr 11, 2024
·
Updated

Fixed bug GHSA-h746-cjrr-wfmr (passwordverify can erroneously return true, opening ATO risk). (CVE-2024-3096)

Other sources

If a password stored with passwordhash starts with a null byte (\x00), testing a blank string as the password via passwordverify will incorrectly return true.

If a user were able to create a password with a leading null byte (unlikely, but syntactically valid), an attacker could trivially compromise the victim's account by attempting to sign in with a blank string.

— Red Hat

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 passwordhash() starts with a null byte (\x00), testing a blank string as the password via passwordverify() will incorrectly return true.

— NVD

PHP function passwordverify can erroneously return true when argument contains NUL

— Microsoft

Affected Software

25 affected componentsFixes available
PHP PHP<8.1.28
8.1.28
redhat/php<8.1.28
8.1.28
redhat/php<8.2.18
8.2.18
redhat/php<8.3.6
8.3.6
PHP PHP>=8.1.0<8.1.28
PHP PHP>=8.2.0<8.2.18
PHP PHP>=8.3.0<8.3.5
Debian Debian Linux=10.0
Microsoft cbl2 php 8.1.22-2<8.1.28-1
8.1.28-1
Microsoft cbl2 php 8.1.28-1<8.1.28-1
8.1.28-1
Microsoft azl3 php 8.1.22-2<8.3.4-1
8.3.4-1
Microsoft azl3 php 8.3.4-1<8.3.4-1
8.3.4-1
debian/php8.2<8.2.18-1~deb12u1
8.2.18-1~deb12u1
debian/php8.2
8.2.32-1~deb12u18.2.35-1~deb12u1
alpine/php81<8.1.28-r0
8.1.28-r0
alpine/php82<8.2.18-r0
8.2.18-r0
alpine/php82<8.2.18-r0
8.2.18-r0
alpine/php82<8.2.18-r0
8.2.18-r0
alpine/php82<8.2.18-r0
8.2.18-r0
alpine/php83<8.3.6-r0
8.3.6-r0
alpine/php83<8.3.5-r0
8.3.5-r0
alpine/php83<8.3.5-r0
8.3.5-r0
alpine/php83<8.3.5-r0
8.3.5-r0
alpine/php83<8.3.5-r0
8.3.5-r0
alpine/php83<8.3.5-r0
8.3.5-r0

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade PHP to a version that resolves this vulnerability.

    Fixed in 8.1.28
  2. Upgrade

    Upgrade redhat/php to a version that resolves this vulnerability.

    Fixed in 8.1.28
  3. Upgrade

    Upgrade redhat/php to a version that resolves this vulnerability.

    Fixed in 8.2.18
  4. Upgrade

    Upgrade redhat/php to a version that resolves this vulnerability.

    Fixed in 8.3.6
  5. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 8.1.28-1
  6. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 8.3.4-1
  7. Upgrade

    Upgrade debian/php8.2 to a version that resolves this vulnerability.

    Fixed in 8.2.18-1~deb12u1
  8. Upgrade

    Upgrade debian/php8.2 to a version that resolves this vulnerability.

    Fixed in 8.2.32-1~deb12u1Fixed in 8.2.35-1~deb12u1
  9. Upgrade

    Upgrade alpine/php81 to a version that resolves this vulnerability.

    Fixed in 8.1.28-r0
  10. Upgrade

    Upgrade alpine/php82 to a version that resolves this vulnerability.

    Fixed in 8.2.18-r0
  11. Upgrade

    Upgrade alpine/php83 to a version that resolves this vulnerability.

    Fixed in 8.3.6-r0
  12. Upgrade

    Upgrade alpine/php83 to a version that resolves this vulnerability.

    Fixed in 8.3.5-r0
  13. Upgrade

    Upgrade PHP to a version that resolves this vulnerability.

    Fixed in 8.2.18
  14. Upgrade

    Upgrade PHP to a version that resolves this vulnerability.

    Fixed in 8.3.5

Event History

Apr 11, 2024
CVE Published
via PHP·12:00 AM
Apr 29, 2024
CVE Published
via MITRE·03:42 AM
Data Sourced
via MITRE·03:42 AM
DescriptionSeverityWeakness
Data Sourced
via NVD·04:15 AM
DescriptionSeverityWeaknessAffected Software
Data Sourced
via OSV·04:15 AM
DescriptionSeverityAffected Software
Data Sourced
via Microsoft·07:00 AM
DescriptionSeverityWeaknessAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Peer vulnerabilities

Found alongside the following vulnerabilities.

Frequently Asked Questions

1

What is the severity of CVE-2024-3096?

CVE-2024-3096 has a moderate severity level due to the potential for unauthorized access if exploited.

2

How do I fix CVE-2024-3096?

To fix CVE-2024-3096, update to the recommended versions of PHP: 7.4.33-1+deb11u5, 8.2.20-1~deb12u1, 8.2.23, or 8.1.28.

3

What does CVE-2024-3096 affect?

CVE-2024-3096 affects the PHP password_verify function, particularly when handling passwords with null bytes.

4

What issues can arise from CVE-2024-3096?

CVE-2024-3096 can lead to an authorization token (ATO) risk if blank strings are incorrectly accepted as valid passwords.

5

Which PHP versions are vulnerable to CVE-2024-3096?

The vulnerable PHP versions include 7.4, 8.1.x, and 8.2.x prior to their respective patched versions.

Company

Resources

Contact

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