CVE-2026-107218
MEDIUM 5.3Excelize 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.
No known exploitation, public exploit, or elevated probability at this time. Track for changes.
Exploitation likelihood
0.3%chance of exploitation in 30 days · 24th percentile
Impact if exploited
5.3CVSS 3.1 · MEDIUM
- ConfidentialityNone
- IntegrityNone
- AvailabilityLow
What an attacker needs
- ✓Access: Reachable over the network — no local access needed
- ✓Privileges: No account or privileges required
- ✓User interaction: No user interaction needed
- ✓Complexity: No special conditions — reliably repeatable
✓ lowers the bar for an attacker · ⚠ raises it
Proof of concept
No public PoC is currently catalogued.
Search for new PoCs
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Tracked sources are checked daily for recent CVEs, including PoCs published after the original disclosure. A later release appears after a tracked source lists it and a refresh succeeds.
Data snapshot:
Weakness (CWE)
- CWE-129: : Improper Validation of Array Index
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
References and research data (JSON)
Packages and version ranges
Each advisory describes its own package and affected ranges. A boundary applies to that range; it is not a universal upgrade recommendation.
github.com/xuri/excelize/v2 Go
pkg:golang/github.com/xuri/excelize/v2
SEMVER range- Introduced version (included): 2.10.1
- Fixed boundary (excluded): 2.11.1-0.20260908032718-ecd99d761fe0
GitHub Advisory Database · GHSA-8jjq-8j9w-m2v6 · Updated 2026-10-07T20:30:05.877569663ZAdditional upstream package constraints
{ "database": { "source": "https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/10/GHSA-8jjq-8j9w-m2v6/GHSA-8jjq-8j9w-m2v6.json" } }
Known Affected Software Configurations
| Vendor | Product | Version range |
|---|---|---|
| Excelize | Excelize | ≥ 2.10.1 and ≤ 2.11.0 |
All CVSS metrics
- MEDIUM 5.3 v3.1 · CNA Primary
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L - MEDIUM 5.3 v3.1 · NVD Secondary
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
References
Exploit-tagged references (not proof of a PoC)
- https://github.com/qax-os/excelize/security/advisories/GHSA-8jjq-8j9w-m2v6 CVE record · GitHub_M · Updated 2026-10-07T18:29:38.606Z
NVD · CVE-2026-107218 · Updated 2026-10-13T14:23:29.317
GitHub Advisory Database · GHSA-8jjq-8j9w-m2v6
GitHub Advisory Database · GHSA-8jjq-8j9w-m2v6 · Updated 2026-10-07T20:30:05.877569663Z
Patches & mitigations
- https://github.com/qax-os/excelize/pull/2390 CVE record · GitHub_M · Updated 2026-10-07T18:29:38.606Z
NVD · CVE-2026-107218 · Updated 2026-10-13T14:23:29.317
GitHub Advisory Database · GHSA-8jjq-8j9w-m2v6
GitHub Advisory Database · GHSA-8jjq-8j9w-m2v6 · Updated 2026-10-07T20:30:05.877569663Z - https://github.com/qax-os/excelize/commit/ecd99d761fe0489f1ed308e2f7dc2e0502d1a396 CVE record · GitHub_M · Updated 2026-10-07T18:29:38.606Z
NVD · CVE-2026-107218 · Updated 2026-10-13T14:23:29.317
GitHub Advisory Database · GHSA-8jjq-8j9w-m2v6
GitHub Advisory Database · GHSA-8jjq-8j9w-m2v6 · Updated 2026-10-07T20:30:05.877569663Z
Advisories
- https://osv.dev/vulnerability/GHSA-8jjq-8j9w-m2v6 GitHub Advisory Database · GHSA-8jjq-8j9w-m2v6
GitHub Advisory Database · GHSA-8jjq-8j9w-m2v6 · Updated 2026-10-07T20:30:05.877569663Z - https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-94548 EUVD · EUVD-2026-94548
Technical & other
- https://github.com/qax-os/excelize GitHub Advisory Database · GHSA-8jjq-8j9w-m2v6
GitHub Advisory Database · GHSA-8jjq-8j9w-m2v6 · Updated 2026-10-07T20:30:05.877569663Z