CVE-2019-11044 | link() silently truncates after a null byte on Windows

Exp

In PHP versions 7.2.x below 7.2.26, 7.3.x below 7.3.13 and 7.4.0 on Windows, PHP link() function accepts filenames with embedded \0 byte and treats them as terminating at that byte. This could lead to security vulnerabilities, e.g. in applications checking paths that the code is allowed to access.

Published: 2019-12-23 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2019-11044 is rated High Exploit Risk (63.2/100): CVSS Low severity, with high exploitation likelihood (EPSS 7.97%, 92th percentile). Core evidence: 1 public exploit reference(s) are indexed (Exploit-DB). EPSS rose +1.25% over the last day, indicating growing attacker interest. Mandatory action: Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2019-11044

EDB-ID Source Kind Published Link
nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2019-11044

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 2026-03-04 6.72% 7.97% +1.25%
2 2026-03-01 7.97% 6.72% -1.25%
3 2026-02-19 7.97%

Full EPSS history (50 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2019-11044

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
3.7 3.1 LOW
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
2.2 1.4 [email protected]
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
3.9 3.6 [email protected]
5.0 2.0 MEDIUM
AV:N/AC:L/Au:N/C:P/I:N/A:N Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:N)
No integrity impact.
Availability impact (A:N)
No availability impact.
10.0 2.9 [email protected]

Weakness enumeration for CVE-2019-11044

OS Trackers for CVE-2019-11044

vendor priority summary link
redhat https://access.redhat.com/security/cve/CVE-2019-11044
ubuntu low CVE-2019-11044 low priority: Ubuntu including 4 source packages (php5, php7.0, php7.2, php7.3), 24 status rows across 6 suites (bionic, disco, eoan, trusty, upstream, xenial): DNE 15, not-affected 8, needs-triage 1. https://ubuntu.com/security/CVE-2019-11044

Affected software / configurations for CVE-2019-11044

Vendor Product Version Raw CPE
php php >= 7.2.0, <= 7.2.26 cpe:2.3:a:php:php:*:*:*:*:*:*:*:*
php php >= 7.3.0, <= 7.3.13 cpe:2.3:a:php:php:*:*:*:*:*:*:*:*
php php 7.4.0 cpe:2.3:a:php:php:7.4.0:*:*:*:*:*:*:*
tenable securitycenter < 5.19.0 cpe:2.3:a:tenable:securitycenter:*:*:*:*:*:*:*:*
fedoraproject fedora 30 cpe:2.3:o:fedoraproject:fedora:30:*:*:*:*:*:*:*
fedoraproject fedora 31 cpe:2.3:o:fedoraproject:fedora:31:*:*:*:*:*:*:*

References for CVE-2019-11044

cvelogic Threat Intelligence