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CVE-2025-6491· NVD / CVE Program· CNA php

NULL Pointer Dereference in PHP SOAP Extension via Large XML Namespace Prefix

Noroxi assessment

Priority: Monitor (action score 23/100)

  • 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: 0.99% (FIRST EPSS); higher than 61.8% of all records.
  • 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 8.1.33, 8.2.29, 8.3.23; cbl2 php 8.1.32-1 on CBL Mariner 2.0 8.1.33-1; cbl2 php 8.1.33-1 on CBL Mariner 2.0 8.1.33-1.

Low priority for now. Upgrade to PHP Group PHP 8.1.33, 8.2.29, 8.3.23; cbl2 php 8.1.32-1 on CBL Mariner 2.0 8.1.33-1; cbl2 php 8.1.33-1 on CBL Mariner 2.0 8.1.33-1 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

In PHP versions:8.1.* before 8.1.33, 8.2.* before 8.2.29, 8.3.* before 8.3.23, 8.4.* before 8.4.10 when parsing XML data in SOAP extensions, overly large (>2Gb) XML namespace prefix may lead to null pointer dereference. This may lead to crashes and affect the availability of the target server.

MediumCVSS 5.9 · v3.1—No exploit Fix available
Published
Jul 13, 2025
Updated
Jun 17, 2026
EPSS
0.9% · 61th percentile

Report tools

JSON

Action score

23

Monitor

Low priority for now.

CVSS
23 / 40 · 5.9 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.9%

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
5.9
NVD has not scored this yet; the score shown is the CNA’s.

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

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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

One daily email digest (06:00 UTC); connect a webhook for KEV listings and weaponized exploits instantly.

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Running WordPress? Scan your site free with WP Lens

  • 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 php8.1.0 and later · before 8.1.33
  • php php8.2.0 and later · before 8.2.29
  • php php8.3.0 and later · before 8.3.23
  • php php8.4.0 and later · before 8.4.10

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

    • 8.1.* and later · before 8.1.33affected · semver
    • 8.2.* and later · before 8.2.29affected · semver
    • 8.3.* and later · before 8.3.23affected · semver
    • 8.4.* and later · before 8.4.10affected · semver

Package-level exposure

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

EcosystemPackageAffected rangeFix
AlmaLinux:8apcu-panelbefore 5.1.18-1.module_el8.6.0+2750+78feabcb5.1.18-1.module_el8.6.0+2750+78feabcb
AlmaLinux:8apcu-panelbefore 5.1.23-1.module_el8.10.0+3796+30ed3ef75.1.23-1.module_el8.10.0+3796+30ed3ef7
AlmaLinux:8libzipbefore 1.6.1-1.module_el8.6.0+3239+bedf05081.6.1-1.module_el8.6.0+3239+bedf0508
AlmaLinux:8libzipbefore 1.6.1-1.module_el8.6.0+2750+78feabcb1.6.1-1.module_el8.6.0+2750+78feabcb
AlmaLinux:8libzipbefore 1.7.3-1.module_el8.10.0+3796+30ed3ef71.7.3-1.module_el8.10.0+3796+30ed3ef7
AlmaLinux:8libzipbefore 1.6.1-1.module_el8.10.0+3935+288084251.6.1-1.module_el8.10.0+3935+28808425
AlmaLinux:8libzip-develbefore 1.6.1-1.module_el8.6.0+3239+bedf05081.6.1-1.module_el8.6.0+3239+bedf0508
AlmaLinux:8libzip-develbefore 1.7.3-1.module_el8.10.0+3796+30ed3ef71.7.3-1.module_el8.10.0+3796+30ed3ef7
AlmaLinux:8libzip-develbefore 1.6.1-1.module_el8.10.0+3935+288084251.6.1-1.module_el8.10.0+3935+28808425
AlmaLinux:8libzip-toolsbefore 1.6.1-1.module_el8.6.0+2750+78feabcb1.6.1-1.module_el8.6.0+2750+78feabcb
AlmaLinux:8libzip-toolsbefore 1.7.3-1.module_el8.10.0+3796+30ed3ef71.7.3-1.module_el8.10.0+3796+30ed3ef7
AlmaLinux:8libzip-toolsbefore 1.6.1-1.module_el8.6.0+3239+bedf05081.6.1-1.module_el8.6.0+3239+bedf0508
AlmaLinux:8libzip-toolsbefore 1.6.1-1.module_el8.10.0+3935+288084251.6.1-1.module_el8.10.0+3935+28808425
AlmaLinux:8phpbefore 7.4.33-3.module_el8.10.0+4114+3b36c6187.4.33-3.module_el8.10.0+4114+3b36c618
AlmaLinux:8phpbefore 8.2.30-1.module_el8.10.0+4108+cff354728.2.30-1.module_el8.10.0+4108+cff35472
AlmaLinux:8php-bcmathbefore 7.4.33-3.module_el8.10.0+4114+3b36c6187.4.33-3.module_el8.10.0+4114+3b36c618
AlmaLinux:8php-bcmathbefore 8.2.30-1.module_el8.10.0+4108+cff354728.2.30-1.module_el8.10.0+4108+cff35472
AlmaLinux:8php-clibefore 8.2.30-1.module_el8.10.0+4108+cff354728.2.30-1.module_el8.10.0+4108+cff35472
AlmaLinux:8php-clibefore 7.4.33-3.module_el8.10.0+4114+3b36c6187.4.33-3.module_el8.10.0+4114+3b36c618
AlmaLinux:8php-commonbefore 8.2.30-1.module_el8.10.0+4108+cff354728.2.30-1.module_el8.10.0+4108+cff35472
AlmaLinux:8php-commonbefore 7.4.33-3.module_el8.10.0+4114+3b36c6187.4.33-3.module_el8.10.0+4114+3b36c618
AlmaLinux:8php-dbabefore 7.4.33-3.module_el8.10.0+4114+3b36c6187.4.33-3.module_el8.10.0+4114+3b36c618
AlmaLinux:8php-dbabefore 8.2.30-1.module_el8.10.0+4108+cff354728.2.30-1.module_el8.10.0+4108+cff35472
AlmaLinux:8php-dbgbefore 8.2.30-1.module_el8.10.0+4108+cff354728.2.30-1.module_el8.10.0+4108+cff35472

+96

Same product

php: all records

Other highest-scoring records for the same primary product.

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  • CVE-2018-7584In 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 pa
    65This week
  • CVE-2018-19518University of Washington IMAP Toolkit 2007f on UNIX, as used in imap_open() in PHP and other products, launches an rsh command (by means of
    59Plan
  • CVE-2016-3078Multiple integer overflows in php_zip.c in the zip extension in PHP before 7.0.6 allow remote attackers to cause a denial of service (heap-b
    56Plan

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 PHP8.1.33Vendor (CNA)
PHP Group PHP8.2.29Vendor (CNA)
PHP Group PHP8.3.23Vendor (CNA)
PHP Group PHP8.4.10Vendor (CNA)
cbl2 php 8.1.32-1 on CBL Mariner 2.08.1.33-1 · CBL-Mariner ReleasesMicrosoft (MSRC)
cbl2 php 8.1.33-1 on CBL Mariner 2.08.1.33-1 · CBL-Mariner ReleasesMicrosoft (MSRC)
almalinux:apcu-panel5.1.23-1.module_el9.6.0+151+5f31e576 · AlmaLinux:9Package registry (OSV)
almalinux:php8.3.26-1.module_el9.7.0+197+324afee8 · AlmaLinux:9Package registry (OSV)
almalinux:php-bcmath8.3.26-1.module_el9.7.0+197+324afee8 · AlmaLinux:9Package registry (OSV)
almalinux:php-cli8.3.26-1.module_el9.7.0+197+324afee8 · AlmaLinux:9Package registry (OSV)
almalinux:php-common8.3.26-1.module_el9.7.0+197+324afee8 · AlmaLinux:9Package registry (OSV)
almalinux:php-dba8.3.26-1.module_el9.7.0+197+324afee8 · AlmaLinux:9Package registry (OSV)
almalinux:php-dbg8.3.26-1.module_el9.7.0+197+324afee8 · AlmaLinux:9Package registry (OSV)
almalinux:php-devel8.3.26-1.module_el9.7.0+197+324afee8 · AlmaLinux:9Package registry (OSV)
almalinux:php-embedded8.3.26-1.module_el9.7.0+197+324afee8 · AlmaLinux:9Package registry (OSV)
almalinux:php-enchant8.3.26-1.module_el9.7.0+197+324afee8 · AlmaLinux:9Package registry (OSV)
almalinux:php-ffi8.3.26-1.module_el9.7.0+197+324afee8 · AlmaLinux:9Package registry (OSV)
almalinux:php-fpm8.3.26-1.module_el9.7.0+197+324afee8 · AlmaLinux:9Package registry (OSV)
debian:php7.47.4.33-1+deb11u9 · Debian:11Package registry (OSV)
debian:php8.28.2.29-1~deb12u1 · Debian:12Package registry (OSV)
debian:php8.48.4.10-1 · Debian:13Package registry (OSV)
opensuse:apache2-mod_php77.4.33-150400.4.51.1 · openSUSE:Leap 15.6Package registry (OSV)
opensuse:php77.4.33-150400.4.51.1 · openSUSE:Leap 15.6Package registry (OSV)
opensuse:php7-embed7.4.33-150400.4.51.1 · openSUSE:Leap 15.6Package registry (OSV)
opensuse:php7-fastcgi7.4.33-150400.4.51.1 · openSUSE:Leap 15.6Package registry (OSV)
opensuse:php7-fpm7.4.33-150400.4.51.1 · openSUSE:Leap 15.6Package registry (OSV)
opensuse:php7-test7.4.33-150400.4.51.1 · openSUSE:Leap 15.6Package registry (OSV)
red hat:apcu-panel0:5.1.23-1.module+el9.6.0+22647+1741ae35 · Red Hat:enterprise_linux:9::appstreamPackage registry (OSV)
red hat:php0:8.3.26-1.module+el9.7.0+23549+c13c2ce3 · Red Hat:enterprise_linux:9::appstreamPackage registry (OSV)
red hat:php-bcmath0:8.3.26-1.module+el9.7.0+23549+c13c2ce3 · Red Hat:enterprise_linux:9::appstreamPackage registry (OSV)

+30

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.

  • CVE-2025-14180167 days apartNULL Pointer Dereference in PDO quoting
    32Monitor
  • CVE-2026-7262301 days apartNULL pointer dereference in SOAP apache:Map decoder with missing <value>
    11Monitor
  • CVE-2026-7259301 days apartNull pointer dereference in php_mb_check_encoding() via mb_ereg_search_init()
    8Monitor

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
none
Integrity
none
Availability
high · the service can be disrupted
Attack vector
Network
Attack complexity
High
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality impact
None
Integrity impact
None
Availability impact
High

Weakness class (CWE)

CWE-476 · NULL Pointer Dereference

CVSS vector

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

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✗ → ✓

For records you follow, these changes also arrive as notifications. →

References

Show all references (1 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records