---
cve: "CVE-2026-108358"
severity: "HIGH"
cvss: 8.8
epss: "0.5%"
vendor: "PHPOffice"
kev: false
exploited: false
published: "2026-10-22 18:17:26"
tags: [cve, security, high]
source: tsecurity.de CVE-Dossier
exported: "2026-10-27T18:06:43+01:00"
---

# CVE-2026-108358

> 8.8 HIGH · 🧪 PoC

## Beschreibung

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, XmlScanner::scan in src/PhpSpreadsheet/Reader/Security/XmlScanner.php uses a DOCTYPE detection pattern that accounts for NUL-byte interleaving but not ISO-2022 escape sequences in XLSX XML parts. The escape sequences prevent the scanner from matching the declaration, and XML charset normalization then removes the escape bytes before parsing, exposing a valid DOCTYPE and entity definitions. Processing an attacker-controlled XLSX can therefore cause entity-expansion denial of service on supported PHP versions and can permit local file access or SSRF on PHP before 8.0 or when LIBXML_NOENT is enabled. This issue is fixed in versions 1.30.7, 2.1.19, 2.4.8, 3.10.8, and 5.10.0.

## CNA-Record (Kanon, cvelistV5)

- CNA: **GitHub_M**
- State: PUBLISHED
- Stand: 2026-10-23 21:08:28
- CNA-CVSS: **8.8** (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:H/SC:L/SI:N/SA:N`)

## CISA-Anreicherung (vulnrichment/ADP)

- CISA-SSVC (Coordinator, v2.0.3):
  - Exploitation: **none**
  - Automatable: **yes**
  - Technical Impact: **partial**

## CVSS-Vektor

```
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:H/SC:L/SI:N/SA:N
```

| Metrik | Wert | Bewertung |
|---|---|---|
| AV Angriffsvektor | Netzwerk | bad |
| AC Komplexität | Gering | bad |
| PR Privilegien | Keine | bad |
| UI Interaktion | Keine | bad |

## Schwachstellen-Klasse

- **CWE-611** — Improper Restriction of XML External Entity Reference
  The product processes an XML document that can contain XML entities with URIs that resolve to documents outside of the intended sphere of control, causing the product to embed incorrect documents into its output.
- **CWE-776** — Improper Restriction of Recursive Entity References in DTDs ('XML Entity Expansion')
  The product uses XML documents and allows their structure to be defined with a Document Type Definition (DTD), but it does not properly control the number of recursive definitions of entities.

## Angriffsmuster (CAPEC)

- [CAPEC-221 — Data Serialization External Entities Blowup](https://capec.mitre.org/data/definitions/221.html)

## Patch verfügbar (OSV)

- f5dd9c1f084d336ea63cf53099533e061a9c157a
- eb2ad61ccffa21bdc77481c69403f2bed5b13e5b

## Referenzen

- <https://github.com/PHPOffice/PhpSpreadsheet/security/advisories/GHSA-3x94-m842-937c>
- <https://github.com/PHPOffice/PhpSpreadsheet/commit/299993894dce37aa3b64aa23e9a3f4bb77ab0e66>
- <https://github.com/PHPOffice/PhpSpreadsheet/commit/89f455c133e1a7e2d4abfadc43ce29eb7450d781>
- <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>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/sicherheitsluecken/cve-2026-108358/) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI WID (CSAF)_