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

{
  "id": "9657ab589571f99dc09952f8f3f513196ece3998cd38c664997554fbcb81f02e",
  "url": "https://osv.dev/vulnerability/GHSA-rxcj-4pj5-74gr",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "Excelize: GetConditionalFormats indexes conditional-formatting rule sub-elements with no length or nil check",
    "summary": "## Summary `GetConditionalFormats` reads sub-elements of a `` straight out of `xl/worksheets/sheetN.xml` and indexes them without checking length, and in one case without checking for nil. Three rule types are affected: `cellIs`, `dataBar` and `colorScale`. A workbook with a rule that is missing a child a real Excel file would always have panics the call. ## Where it is All three sinks are in `styles.go`, at the same line numbers in v2.11.0 and on master `d552a7e`. All three are reached from `GetConditionalFormats` through `styles.go:3271`. `styles.go:3003`, in `extractCondFmtCellIs`: ```go format.Value = c.Formula[0] ``` The branch above it handles `len(c.Formula) == 2`; this one is the fallback and does not check that there is a formula at all, so a `cellIs` rule with no `` child indexes an empty slice. `styles.go:3132`, in the colorScale extractor: ```go values := len(c.ColorScale.Cfvo) ``` `c.ColorScale` is a `*xlsxColorScale` and is nil when the `` element has no `` child. Lines 3148 and 3153 then index `Cfvo[1]` and `Cfvo[2]` in the three-colour branch with no length check either. `styles.go:3186`, `:3188` and `:3190`, in the dataBar extractor: ```go format.MinType = c.DataBar.Cfvo[0].Type ... format.BarColor = \"#\" + f.getThemeColor(c.DataBar.Color[0]) ``` The guard here is `c.DataBar != nil`, which says nothing about the length of `Cfvo` or `Color`, so an empty `` element reaches all three. ## Who the attacker is Anyone who can hand a spreadsheet to a service that open",
    "evidence": "osv:GHSA-rxcj-4pj5-74gr",
    "products": [
      {
        "name": {
          "value": "github.com/xuri/excelize/v2",
          "evidence": "/affected/0/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "2.11.1-0.20260812075026-be7a16390fa6",
            "evidence": "/affected/0/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "medium",
    "structured": {
      "id": "GHSA-rxcj-4pj5-74gr",
      "aliases": [
        "CVE-2026-107222",
        "GHSA-rxcj-4pj5-74gr"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "type": "SEMVER",
              "events": [
                {
                  "introduced": "2.7.0"
                },
                {
                  "fixed": "2.11.1-0.20260812075026-be7a16390fa6"
                }
              ]
            }
          ],
          "package": {
            "name": "github.com/xuri/excelize/v2",
            "purl": "pkg:golang/github.com/xuri/excelize/v2",
            "ecosystem": "Go"
          },
          "database_specific": {
            "source": "https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/10/GHSA-rxcj-4pj5-74gr/GHSA-rxcj-4pj5-74gr.json"
          }
        }
      ],
      "modified": "2026-10-07T20:30:05.876273601Z",
      "provider": "osv",
      "references": [
        "https://github.com/qax-os/excelize/security/advisories/GHSA-rxcj-4pj5-74gr",
        "https://github.com/qax-os/excelize/pull/2375",
        "https://github.com/qax-os/excelize/commit/be7a16390fa69c71d3ca618c741d1a2b5ed362cd",
        "https://github.com/qax-os/excelize"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-129",
          "CWE-476"
        ],
        "severity": "MODERATE",
        "github_reviewed": true,
        "nvd_published_at": null,
        "github_reviewed_at": "2026-10-07T20:22:54Z"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-107222",
        "evidence": "/aliases"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 97230,
  "published_at": "2026-10-07T20:22:54+00:00"
}