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NVD / CVE Program· CNA php

CVE-2026-17545: PHP on Windows: Reserved Device Names Are Not Rejected Before File/Stream I/O which can cause DoS

Noroxi assessment

Priority: Monitor (action score 27/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 0.36% (FIRST EPSS).
  • Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. Special conditions such as timing or configuration are required.
  • Fixed version: PHP Group PHP 8.2.34, 8.3.35, 8.4.26; azl3 php 8.3.33-1 on Azure Linux 3.0 8.3.35-1.

Low priority for now. Upgrade to PHP Group PHP 8.2.34, 8.3.35, 8.4.26; azl3 php 8.3.33-1 on Azure Linux 3.0 8.3.35-1 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

On Windows, PHP's filesystem and stream APIs do not reject reserved device names such as CON, PRN, AUX, NUL, COM1 to COM9, LPT1 to LPT9, CONIN$ and CONOUT$ when they appear as a component of a path. An attacker-controlled filename therefore reaches CreateFileW() and opens a device instead of the regular file the application expected, which can block or hang the request and exhaust worker processes.

MediumCVSS 6.9 · v4.0—No exploit Fix available
Published
Sep 25, 2026
Updated
Oct 23, 2026
EPSS
0.3% · 30th percentile

Report tools

JSON

Action score

27

Monitor

Low priority for now.

CVSS
27 / 40 · 6.9 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.3%

CISA SSVC decision

Exploitation
proof of concept
Automatable
no
Technical impact
partial

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD
—
CNA · php
6.9
NVD has not scored this yet; the score shown is the CNA’s.

CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:H

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • A fix has been released

If any of these changes, we'll tell you in the daily email digest.

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When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

VendorProduct
phpphp
microsoftwindows

Using php? Add it to your stack and be the first to know about CVEs like this one. (PHP)

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When you'll hear from us

  • when a new CVE affecting this product is published
  • when a record in your stack enters KEV or gets exploit code

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  • Stack alerts: add the products and versions you run, get the new CVEs that affect them
  • Uptime monitoring: 1 site, instant email when it goes down
  • Add your domain: subdomains and takeover risk scanned every week (1 domain)
  • 10 scans an hour on the security tools (3 a day without an account), an API key and MCP
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Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • php php8.2.0 and later · before 8.2.34
  • php php8.3.0 and later · before 8.3.35
  • php php8.4.0 and later · before 8.4.26
  • php php8.5.0 and later · before 8.5.11

Versions reported by the vendor

Affected version ranges reported by the assigning authority (php). Independent of NVD's CPE analysis and usually ahead of it.

  • PHP Group PHP

    • 8.2.* and later · before 8.2.34affected · semver
    • 8.3.* and later · before 8.3.35affected · semver
    • 8.4.* and later · before 8.4.26affected · semver
    • 8.5.* and later · before 8.5.11affected · semver

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
openSUSE:Tumbleweedphp8before 8.5.11-1.18.5.11-1.1
Red Hat:hummingbird:1phpbefore 0:8.5.11-2.hum10:8.5.11-2.hum1
Red Hat:hummingbird:1php-bcmathbefore 0:8.5.11-2.hum10:8.5.11-2.hum1
Red Hat:hummingbird:1php-clibefore 0:8.5.11-2.hum10:8.5.11-2.hum1
Red Hat:hummingbird:1php-commonbefore 0:8.5.11-2.hum10:8.5.11-2.hum1
Red Hat:hummingbird:1php-dbabefore 0:8.5.11-2.hum10:8.5.11-2.hum1
Red Hat:hummingbird:1php-dbgbefore 0:8.5.11-2.hum10:8.5.11-2.hum1
Red Hat:hummingbird:1php-develbefore 0:8.5.11-2.hum10:8.5.11-2.hum1
Red Hat:hummingbird:1php-embeddedbefore 0:8.5.11-2.hum10:8.5.11-2.hum1
Red Hat:hummingbird:1php-enchantbefore 0:8.5.11-2.hum10:8.5.11-2.hum1
Red Hat:hummingbird:1php-ffibefore 0:8.5.11-2.hum10:8.5.11-2.hum1
Red Hat:hummingbird:1php-fpmbefore 0:8.5.11-2.hum10:8.5.11-2.hum1
Red Hat:hummingbird:1php-gdbefore 0:8.5.11-2.hum10:8.5.11-2.hum1
Red Hat:hummingbird:1php-gmpbefore 0:8.5.11-2.hum10:8.5.11-2.hum1
Red Hat:hummingbird:1php-intlbefore 0:8.5.11-2.hum10:8.5.11-2.hum1
Red Hat:hummingbird:1php-ldapbefore 0:8.5.11-2.hum10:8.5.11-2.hum1
Red Hat:hummingbird:1php-mbstringbefore 0:8.5.11-2.hum10:8.5.11-2.hum1
Red Hat:hummingbird:1php-mysqlndbefore 0:8.5.11-2.hum10:8.5.11-2.hum1
Red Hat:hummingbird:1php-odbcbefore 0:8.5.11-2.hum10:8.5.11-2.hum1
Red Hat:hummingbird:1php-pdobefore 0:8.5.11-2.hum10:8.5.11-2.hum1
Red Hat:hummingbird:1php-pdo-dblibbefore 0:8.5.11-2.hum10:8.5.11-2.hum1
Red Hat:hummingbird:1php-pdo-firebirdbefore 0:8.5.11-2.hum10:8.5.11-2.hum1
Red Hat:hummingbird:1php-pgsqlbefore 0:8.5.11-2.hum10:8.5.11-2.hum1
Red Hat:hummingbird:1php-processbefore 0:8.5.11-2.hum10:8.5.11-2.hum1

+5

Same product

php: all records

Other highest-scoring records for the same primary product.

  • CVE-2024-4577Argument Injection in PHP-CGIKEV
    99Now
  • CVE-2019-11043Underflow in PHP-FPM can lead to RCEKEV
    99Now
  • CVE-2012-1823sapi/cgi/cgi_main.c in PHP before 5.3.12 and 5.4.x before 5.4.2, when configured as a CGI script (aka php-cgi), does not properly handle queKEV
    99Now

Published before and after this one in the same product

  • ← EarlierCVE-2025-14181Sep 25, 2026 · Integer overflow to buffer overflow in soap HTTP parsing
    26Monitor
  • ← EarlierCVE-2025-1218Sep 25, 2026 · Various packet overreads in mysqlnd_writeprotocol.c
    23Monitor
  • Later →CVE-2026-6103Sep 25, 2026 · Phar TAR phar_tar_number() Integer Overflow - Archive Entry Injection
    13Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
PHP Group PHP8.2.34Vendor (CNA)
PHP Group PHP8.3.35Vendor (CNA)
PHP Group PHP8.4.26Vendor (CNA)
PHP Group PHP8.5.11Vendor (CNA)
azl3 php 8.3.33-1 on Azure Linux 3.08.3.35-1 · Release NotesMicrosoft (MSRC)
opensuse:php88.5.11-1.1 · openSUSE:TumbleweedPackage registry (OSV)
red hat:php0:8.5.11-2.hum1 · Red Hat:hummingbird:1Package registry (OSV)
red hat:php-bcmath0:8.5.11-2.hum1 · Red Hat:hummingbird:1Package registry (OSV)
red hat:php-cli0:8.5.11-2.hum1 · Red Hat:hummingbird:1Package registry (OSV)
red hat:php-common0:8.5.11-2.hum1 · Red Hat:hummingbird:1Package registry (OSV)
red hat:php-dba0:8.5.11-2.hum1 · Red Hat:hummingbird:1Package registry (OSV)
red hat:php-dbg0:8.5.11-2.hum1 · Red Hat:hummingbird:1Package registry (OSV)
red hat:php-devel0:8.5.11-2.hum1 · Red Hat:hummingbird:1Package registry (OSV)
red hat:php-embedded0:8.5.11-2.hum1 · Red Hat:hummingbird:1Package registry (OSV)
red hat:php-enchant0:8.5.11-2.hum1 · Red Hat:hummingbird:1Package registry (OSV)
red hat:php-ffi0:8.5.11-2.hum1 · Red Hat:hummingbird:1Package registry (OSV)
red hat:php-fpm0:8.5.11-2.hum1 · Red Hat:hummingbird:1Package registry (OSV)
red hat:php-gd0:8.5.11-2.hum1 · Red Hat:hummingbird:1Package registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

No nightly-computed relations.

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

Attack conditions

  • Anyone who can reach it over the internet can trigger it.
  • No account or password is required.
  • No user action is required.
  • Special conditions such as timing or configuration are required.

If successful

Confidentiality
Integrity
Availability
Attack vector
Network
Attack complexity
High
Privileges required
None
User interaction
None
Scope
X

Weakness class (CWE)

CWE-67 · Improper Handling of Windows Device Names

CVSS vector

CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

nvd-secondary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

MITRE has no CAPEC/ATT&CK mapping for this CWE.

Change log

  1. Fix✗ → ✓

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