CVE-2026-34084

Year

2026

Published

May 5, 2026

Known Affected Devices

CVSS Score

N/A

What is CVE-2026-34084?

PhpSpreadsheet is a library for reading and writing spreadsheet files. In versions 1.30.2 and earlier, 2.0.0 through 2.1.14, 2.2.0 through 2.4.3, 3.3.0 through 3.10.3, and 4.0.0 through 5.5.0, when the filename argument to IOFactory::load() is user-controlled, an attacker can supply a PHP stream wrapper path (such as phar://, ftp://, or ssh2.sftp://) that passes the is_file() check in File::assertFile(). The phar:// wrapper triggers deserialization of the PHAR metadata, which can lead to remote code execution if a suitable gadget chain is available in the application. The ftp:// and ssh2.sftp:// wrappers can be used for server-side request forgery. This issue has been fixed in versions 1.30.3, 2.1.15, 2.4.4, 3.10.4, and 5.6.0.

FAQ

How severe is CVE-2026-34084?

CVE-2026-34084 has a CVSS score of N/A/10, rated as Unknown. Review the affected products list and apply vendor patches.

What does the CVSS score mean for CVE-2026-34084?

CVSS (Common Vulnerability Scoring System) rates vulnerability severity from 0.0 to 10.0. CVE-2026-34084 scores N/A/10 (Unknown). Scores 9.0–10.0 are Critical, 7.0–8.9 are High, 4.0–6.9 are Medium, and below 4.0 are Low.

Which devices are affected by CVE-2026-34084?

The list of devices confirmed to be affected by CVE-2026-34084 is shown in the "Affected Devices" section above. Check your firmware version against the vendor security advisory and apply the latest patch.

How do I fix or mitigate CVE-2026-34084?

Apply the latest firmware or software update from the vendor. Check the References section above for official advisories and patch notes. If no patch is available, consider disabling the affected feature or isolating the device from untrusted networks.