CVE-2026-107218
Excelize: RIGHT() on supplementary-plane text slices with a negative index and panics
Description
Excelize is a Go language library for reading and writing Microsoft Excel spreadsheets. From 2.10.1 to 2.11.0, RIGHT validates the requested length with UTF-16 code-unit counts but slices a rune array using Unicode code-point counts. RIGHT reaches leftRight through CalcCellValue, where countUTF16String validates one unit but utf8.RuneCountInString supplies the slice index in another. When RIGHT evaluates supplementary-plane text with a requested character count between the rune count and UTF-16 code-unit count, the inconsistent units produce a negative rune-slice index, allowing an attacker to panic during formula evaluation. No fixed version is available as of this review.
INFO
Published Date :
Oct. 7, 2026, 7:17 p.m.
Last Modified :
Oct. 7, 2026, 7:17 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | MEDIUM | MITRE-CVE | ||||
| CVSS 3.1 | MEDIUM | [email protected] |
Solution
- Mitigate or replace the affected library.
- Monitor for an updated version.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-107218.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-107218 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-107218
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-107218 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-107218 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by [email protected]
Oct. 07, 2026
Action Type Old Value New Value Added Description Excelize is a Go language library for reading and writing Microsoft Excel spreadsheets. From 2.10.1 to 2.11.0, RIGHT validates the requested length with UTF-16 code-unit counts but slices a rune array using Unicode code-point counts. RIGHT reaches leftRight through CalcCellValue, where countUTF16String validates one unit but utf8.RuneCountInString supplies the slice index in another. When RIGHT evaluates supplementary-plane text with a requested character count between the rune count and UTF-16 code-unit count, the inconsistent units produce a negative rune-slice index, allowing an attacker to panic during formula evaluation. No fixed version is available as of this review. Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L Added CWE CWE-129 Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/107xxx/CVE-2026-107218.json">CVE-2026-107218</a> Added Reference https://github.com/qax-os/excelize/commit/ecd99d761fe0489f1ed308e2f7dc2e0502d1a396 Added Reference https://github.com/qax-os/excelize/pull/2390 Added Reference https://github.com/qax-os/excelize/security/advisories/GHSA-8jjq-8j9w-m2v6