PhpSpreadsheet: XmlScanner Bypass via ISO-2022 Escape Sequences Allows XXE and Denial of Service
High-risk advisory
CVE-2026-108358
Summary
PhpSpreadsheet: XmlScanner Bypass via ISO-2022 Escape Sequences Allows XXE and Denial of Service
Why it matters
GitHub has published a reviewed security advisory for phpoffice/phpspreadsheet. Prioritize it with other application dependency updates, especially because EPSS places it in the 41% percentile.
Operator check
Check whether phpoffice/phpspreadsheet is present in application dependency manifests, lockfiles, or build images. Review the GitHub advisory and upgrade to a patched version where available. CVSS score: 8.8. EPSS probability: 0.5%; percentile: 41%.
Sources
PatchBrief uses public sources. It does not scan environments, verify exposure, or replace vendor guidance.