CVE-2026-108360 PhpSpreadsheet: SSRF whitelist bypass via unre-validated HTTP redirect in Drawing::setPath external image loading

What is CVE-2026-108360?

CVE-2026-108360 is a medium-severity vulnerability in PHPOffice PhpSpreadsheet, published on 22 Oct 2026.

Official description

PhpSpreadsheet is a pure PHP library for reading and writing spreadsheet files. Prior to 1.30.7, 2.1.19, 2.4.8, 3.10.8, and 5.10.0, Worksheet\Drawing::setPath validates only the initial external-image URL with setIsWhitelisted when setAllowExternalImages is enabled. The HTTP stream context permits PHP to follow a redirect without applying the callback to the redirected URL, so a permitted image host can redirect the server to an internal address and cause a blind GET request. The response body is not returned to the attacker because the reader validates the downloaded content as an image and removes the temporary file, but internal GET-driven endpoints, network reachability, and cloud metadata endpoints may be reached. This issue is fixed in versions 1.30.7, 2.1.19, 2.4.8, 3.10.8, and 5.10.0.

Weakness: CWE-918, CWE-863

Which versions are affected by CVE-2026-108360?

10 open source packages ship an affected version, including phpoffice/phpspreadsheet.

How do I fix CVE-2026-108360?

Upgrade phpoffice/phpspreadsheet to a fixed version for your release line: 1.30.7, 2.1.19, 2.4.8 or 3.10.8.

Is CVE-2026-108360 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-108360 exists.

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as GHSA-2phh-27fw-q4gc.