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TI-2026-69267 Aliases CVE-2026-107218GHSA-8jjq-8j9w-m2v6

Negative index panic in Excelize RIGHT() on supplementary-plane text

Priority LOW 30CWE-129Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
None · None · Low
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub.

Summary

Excelize, a Go library for reading and writing Microsoft Excel spreadsheets, from 2.10.1 through 2.11.0 has an improper array index validation flaw (CWE-129) in its RIGHT() formula function. RIGHT checks the requested length with UTF-16 code-unit counts but slices text with Unicode code-point counts, so supplementary-plane text produces a negative slice index. An unauthenticated remote attacker can cause a panic during formula evaluation without user interaction. A public exploit is linked in the references.

Written with Claude Haiku 5.5 from the sources below · 2026-10-29

Description from the CNA

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00309 23rd percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Fixed github.com/xuri/excelize/v2 (Go): 2.11.1-0.20260908032718-ecd99d761fe0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
qax-osexcelize2.10.1 – 2.11.0—No fix listedCNA
—github.com/xuri/excelize/v2 (Go)2.10.1 to before 2.11.1-0.20260908032718-ecd99d761fe02.11.1-0.20260908032718-ecd99d761fe0Patch availableGHSA-8jjq-8j9w-m2v6
  • excelize Vendorqax-os Affected 2.10.1 – 2.11.0 Fixed in — No fix listed CNA
  • github.com/xuri/excelize/v2 (Go) Vendor— Affected 2.10.1 to before 2.11.1-0.20260908032718-ecd99d761fe0 Fixed in 2.11.1-0.20260908032718-ecd99d761fe0 Patch available GHSA-8jjq-8j9w-m2v6

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:excelize:excelize:*:*:*:*:*:go:*:*2.10.1 – 2.11.0Vulnerableqax-os
  • cpe:2.3:a:excelize:excelize:*:*:*:*:*:go:*:* Versions 2.10.1 – 2.11.0 Vulnerable ·qax-os

Remediation

Upgrade github.com/xuri/excelize/v2 to 2.11.1-0.20260908032718-ecd99d761fe0, the fixed version for the Go module. The sources list no fixed version for excelize.

Written with Claude Haiku 5.5 from the sources below · 2026-10-29

  • Fix · GHSA-8jjq-8j9w-m2v6 github.com/xuri/excelize/v2 (Go) Fixed in 2.11.1-0.20260908032718-ecd99d761fe0 Advisory →

Timeline

  1. 2026-10-07 Threatist record created from CVE-2026-107218
  2. 2026-10-07 Alias added: GHSA-8jjq-8j9w-m2v6
  3. 2026-10-07 Fix available: Go/github.com/xuri/excelize/[email protected] · GHSA-8jjq-8j9w-m2v6
  4. 2026-10-07 CVSS score added · GHSA-8jjq-8j9w-m2v6
  5. 2026-10-07 Weakness changed · GHSA-8jjq-8j9w-m2v6
  6. 2026-10-07 4 new references · GHSA-8jjq-8j9w-m2v6
  7. 2026-10-07 CISA SSVC decision points changed

References

Exploit 1

Patch 2

Other 1

  • TI-2026-42325 Excelize: Streaming GetRows row-bound bypass causes attacker-controlled allocation CVSS 4.0HIGH 8.7
  • TI-2026-69266 Integer overflow in Excelize column parsing causes process panic CVSS 3.1HIGH 7.5
  • TI-2026-69263 Excelize crafted OLE files cause memory exhaustion and panic CVSS 3.1HIGH 7.5
  • TI-2026-69262 Unrecoverable panics in Excelize Decrypt on malformed OLE workbooks CVSS 3.1HIGH 7.5
  • TI-2026-69260 Unbounded row number in Excelize lets crafted spreadsheets hang reads CVSS 3.1HIGH 7.5
  • TI-2026-38996 Excelize: Unbounded Row Index Allocation in Worksheet Parser (checkSheet OOM/Panic DoS) CVSS 3.1HIGH 7.5
See all 17 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences