Vulnerability · Published Oct 7, 2026 · Assigned by GitHub_M
CVE-2026-107215Excelize: extractPart allocates attacker-controlled, unbounded and negative-sized buffers from CFB directory entries: remote panic / OOM DoS
High 7.5
In plain English
A high-severity security flaw in excelize from qax-os. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 15% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
Excelize is a Go language library for reading and writing Microsoft Excel spreadsheets. From 2.3.1 to 2.11.0, extractPart allocates a byte slice directly from an attacker-controlled CFB directory-entry size before validating the sector chain or size domain. extractPart trusts the CFB directory entry streamSize for EncryptionInfo and EncryptedPackage allocations before validating the stream. When a crafted OLE compound file declares a negative or extremely large EncryptionInfo or EncryptedPackage stream size, the declared size reaches make with a negative length or forces a multi-gigabyte allocation, allowing an attacker to panic or exhaust process memory. No fixed version is available as of this review.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Go | github.com/360EntSecGroup-Skylar/excelize/v2 | no fix listed | GO-2026-6689 |
| Go | github.com/xuri/excelize/v2 | 2.11.1-0.20260912113515-5f636f9dcde5 | GO-2026-6689 |
| Go | github.com/xuri/excelize/v2 | 2.11.1-0.20260912113515-5f636f9dcde5 | GHSA-x2q3-8cjh-766f |
Affected products (as reported)
Weakness: CWE-789 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
References
- https://github.com/qax-os/excelize/security/advisories/GHSA-x2q3-8cjh-766f x_refsource_CONFIRM
- https://github.com/qax-os/excelize/pull/2396 x_refsource_MISC
- https://github.com/qax-os/excelize/commit/5f636f9dcde55911f14290060b017f0cc88cd694 x_refsource_MISC