CVE-2026-34084Public exploitNetwork attack vector

SSRF and code execution via PHP stream wrappers

Published May 5, 2026 · Updated May 5, 2026

Stream-wrapper injection in PHPOffice PhpSpreadsheet allows remote attackers to cause SSRF or code execution through IOFactory::load(). File::assertFile passes a user-controlled filename to PHP's wrapper-aware is_file check, permitting ftp:// and ssh2.sftp:// requests or phar:// metadata deserialization. Reachability requires an application to pass attacker-controlled filenames, and code execution also requires a usable gadget chain.

CVSS severity9.2
Critical
EPSS probability0.71%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stream-wrapper injection in PHPOffice PhpSpreadsheet allows remote attackers to cause SSRF or code execution through IOFactory::load(). File::assertFile passes a user-controlled filename to PHP's wrapper-aware is_file check, permitting ftp:// and ssh2.sftp:// requests or phar:// metadata deserialization. Reachability requires an application to pass attacker-controlled filenames, and code execution also requires a usable gadget chain.

The record

CVE
CVE-2026-34084
Published
May 5, 2026
Updated
May 5, 2026
Vendor
PHPOffice
Product
PhpSpreadsheet
Classifications
CWE-918, CWE-502, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 5, 2026CVE publishedPublication date reported by the CVE source.
  2. May 5, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=<= 1.30.2
  2. Affected versionversion=>= 2.0.0, <= 2.1.14
  3. Affected versionversion=>= 2.2.0, <= 2.4.3
  4. Affected versionversion=>= 3.3.0, <= 3.10.3
  5. Affected versionversion=>= 4.0.0, <= 5.5.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

PHPOffice · PhpSpreadsheetversion=<= 1.30.2; version=>= 2.0.0, <= 2.1.14; version=>= 2.2.0, <= 2.4.3; version=>= 3.3.0, <= 3.10.3; version=>= 4.0.0, <= 5.5.0

Published CVSS scores

9.2GitHub, Inc.CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
9.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-918Server-Side Request Forgery (SSRF)
CWE-502Deserialization of Untrusted Data
T1190Exploit Public-Facing Application

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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