Excelize: GetConditionalFormats indexes conditional-formatting rule sub-elements with no length or nil check

[ Why it matters ]Priority signals

• Public proof-of-concept exploit exists (CISA SSVC)

[ Description ]Official description

Excelize is a Go language library for reading and writing Microsoft Excel spreadsheets. From 2.7.0 to 2.11.0, conditional-format extraction indexes required child slices or dereferences an optional colorScale child without validating malformed rule structure. GetConditionalFormats reaches extractCondFmtCellIs and also indexes ColorScale.Cfvo, DataBar.Cfvo, and DataBar.Color without complete structural checks. When a crafted worksheet supplies a cellIs, dataBar, or colorScale rule missing expected children and the application calls GetConditionalFormats, missing formula, color, value-object, or colorScale data reaches an out-of-range index or nil dereference, allowing an attacker to panic and terminate an unprotected process. No fixed version is available as of this review.

[ Fixes ]Fixes and patches

• github.com/xuri/excelize/v2 2.11.1-0.20260812075026-be7a16390fa6Fixed version · GitHub Advisories · go package github.com/xuri/excelize/v2: upgrade to 2.11.1-0.20260812075026-be7a16390fa6 or later (affected >= 2.7.0, < 2.11.1-0.20260812075026-be7a16390fa6)
• Patch on github.comVendor patch or bulletin · NVD · Reference tagged 'Patch' by NVD
• Patch on github.comVendor patch or bulletin · NVD · Reference tagged 'Patch' by NVD

[ Packages ]Affected open-source packages

• github.com/xuri/excelize/v2 goAffected >= 2.7.0, < 2.11.1-0.20260812075026-be7a16390fa6 · fixed in 2.11.1-0.20260812075026-be7a16390fa6 · GHSA-rxcj-4pj5-74gr

[ References ]References

• github.com/qax-os/excelize/commit/be7a16390fa69c71d3ca618c741d1a2b5ed362cdExploitPatch
• github.com/qax-os/excelize/pull/2375Issue TrackingPatch
• github.com/qax-os/excelize/security/advisories/GHSA-rxcj-4pj5-74grExploitVendor Advisory