What is CVE-2018-7584?

CVE-2018-7584 is a critical-severity vulnerability in PHP, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 9.8/10. Published 2018-03-01.

How severe is CVE-2018-7584?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Is CVE-2018-7584 known to be exploited?

1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

Buffer overflow in PHP

CVE-2018-7584

In PHP through 5.6.33, 7.0.x before 7.0.28, 7.1.x through 7.1.14, and 7.2.x through 7.2.2, there is a stack-based buffer under-read while parsing an HTTP response in the php_stream_url_wrap_http_ex function in ext/standard/http_fopen_wrapper.c. This subsequently results in copying a large string.

Vulnerability class: Buffer Overflow

Published 2018-03-01 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.873 (99.8th percentile), scored 2026-10-16.

High probability of exploitation in the next 30 days — patch promptly. 100th percentile — 99.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.836 · newest: 0.873 · change: +0.038

Affected products

PHP
Canonical Ubuntu Linux — versions 12.04, 14.04, 16.04
Debian Linux — versions 7.0, 8.0, 9.0

Weakness classification (CWE)

CWE-119 — Improper Restriction of Operations within the Bounds of a Memory Buffer

Public proof-of-concept exploits

ARPSyndicate/cve-scores

References

usn.ubuntu.com/3600-1/ (vendor-advisory, Third Party Advisory)
www.debian.org/security/2018/dsa-4240 (vendor-advisory, Third Party Advisory)
bugs.php.net/bug.php (Issue Tracking)
lists.debian.org/debian-lts-announce/2018/03/msg00030.html (mailing-list, Mailing List, Third Party Advisory)
www.tenable.com/security/tns-2018-12 (Third Party Advisory)
www.tenable.com/security/tns-2018-03 (Third Party Advisory)
www.securitytracker.com/id/1041607 (VDB Entry, Third Party Advisory, vdb-entry)
github.com/php/php-src/commit/523f230c831d7b33353203fa34aee4e92ac12bba (Patch)
www.exploit-db.com/exploits/44846/ (Exploit, VDB Entry, Third Party Advisory, exploit)
php.net/ChangeLog-7.php (Release Notes)

Frequently asked questions

What is CVE-2018-7584?: CVE-2018-7584 is a critical-severity vulnerability in PHP, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 9.8/10. Published 2018-03-01.
How severe is CVE-2018-7584?: Critical severity. CVSS v3 base score is 9.8 out of 10.
Is CVE-2018-7584 known to be exploited?: 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.