CVE-2023-0567: password_verify() always returns true for some invalid hashes
CSIRTS triage
- What
- The password_verify() function returns true for some invalid hashes, allowing authentication bypass.
- Who is affected
- PHP applications using password_verify() for authentication, all versions affected.
- Urgency
- High severity (CVSS 7.7) authentication bypass; immediate patching required despite no known exploitation.
- Action
- Update PHP to a patched version that correctly validates hashes in password_verify().
AI-assisted analysis generated from the source advisory — verify against the original.
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Details
Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2023-0567
Exploitation outlook
EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.
- Low exploitation riskCVE-2023-05670.95% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 58% of all EPSS-scored CVEs.
Referenced CVEs
| CVE | CSIRTS overview | External |
|---|---|---|
| CVE-2023-0567 | coverage & exploitation status | NVD · CVE.org |
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