In PHP from 8.1.* before 8.1.32, from 8.2.* before 8.2.28, from 8.3.* before 8.3.19, from 8.4.* before 8.4.5, when receiving headers from HTTP server, the headers missing a colon (:) are treated as valid headers even though they are not. This may confuse applications into accepting invalid headers.
Conclusion & alert: CVE-2025-1734 is rated Moderate Risk (50.9/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 0.76%). Mandatory action: Review affected assets and schedule remediation.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).
| # | Date | Old EPSS score | New EPSS score | Delta (New - Old) |
|---|---|---|---|---|
| 1 | 2026-04-22 | 0.72% | 0.76% | +0.04% |
| 2 | 2026-04-21 | 0.76% | 0.72% | -0.04% |
| 3 | 2026-04-20 | — | 0.76% | — |
Full EPSS history (12 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 6.3 | 4.0 | MEDIUM |
|
— | — | [email protected] |
| 5.3 | 3.1 | MEDIUM |
|
3.9 | 1.4 | [email protected] |
| vendor | priority | summary | link |
|---|---|---|---|
alpine
|
medium | CVE-2025-1734: 2 source package rows (php82, php83); 6 state rows across 3 repos (3.21-community, 3.22-community, edge-community); fixed 6, open 0. | https://security.alpinelinux.org/vuln/CVE-2025-1734 |
debian
|
not yet assigned | CVE-2025-1734 not yet assigned priority: Debian including 3 source packages (php7.4, php8.2, php8.4), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. | https://security-tracker.debian.org/tracker/CVE-2025-1734 |
redhat
|
medium | — | https://access.redhat.com/security/cve/CVE-2025-1734 |
suse
|
medium | CVE-2025-1734 severity moderate: SUSE including 459 source package names (8.2.28-48.42:php8-8.2.28-150600.3.16.1, 8.2.28-48.42:php8-cli-8.2.28-150600.3.16.1, …), 1771 product×package rows across 35 product lines (Container bci/php, Container bci/php-apache, … (35 product lines)): Fixed 1606, Known Not Affected 165. | https://www.suse.com/security/cve/CVE-2025-1734/ |
ubuntu
|
medium | CVE-2025-1734 medium priority: Ubuntu including 7 source packages (php5, php7.0, …), 52 status rows across 10 suites (bionic, focal, jammy, noble, oracular, plucky, questing, trusty, upstream, xenial): DNE 36, needs-triage 8, released 8. | https://ubuntu.com/security/CVE-2025-1734 |
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| php | php | >= 8.1.0, < 8.1.32 | cpe:2.3:a:php:php:*:*:*:*:*:*:*:* |
| php | php | >= 8.2.0, < 8.2.28 | cpe:2.3:a:php:php:*:*:*:*:*:*:*:* |
| php | php | >= 8.3.0, < 8.3.19 | cpe:2.3:a:php:php:*:*:*:*:*:*:*:* |
| php | php | >= 8.4.0, < 8.4.5 | cpe:2.3:a:php:php:*:*:*:*:*:*:*:* |
| netapp | ontap | 9 | cpe:2.3:a:netapp:ontap:9:*:*:*:*:*:*:* |
| URL | Tags |
|---|---|
| https://github.com/php/php-src/security/advisories/GHSA-pcmh-g36c-qc44 | Vendor Advisory |
| https://lists.debian.org/debian-lts-announce/2025/03/msg00014.html | |
| https://security.netapp.com/advisory/ntap-20250523-0009/ | Third Party Advisory |