CVE-2026-107218: medium-severity vulnerability in qax-os excelize
Excelize: RIGHT() on supplementary-plane text slices with a negative index and panics
Published
10Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 5.3
exploitation probability
—
observed exploitation
nono source reports it
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.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Affected products
qax-os · excelizeRelated CVEs — qax-os excelize
In the same product, most dangerous first.
CVE-2026-59162MEDIUMExcelize: Negative shared-string index causes panic in GetCellValue and GetRowsEPSS 0.7%CVE-2026-59161HIGHExcelize: Streaming GetRows row-bound bypass causes attacker-controlled allocationEPSS 0.7%CVE-2026-54063HIGHExcelize: Unbounded Row Index Allocation in Worksheet Parser (checkSheet OOM/Panic DoS)EPSS 0.6%CVE-2026-107225MEDIUMExcelize: GetStyle panics on a negative fillId, borderId or fontId in styles.xmlEPSS —CVE-2026-107224MEDIUMExcelize: A Zip64 uncompressed-size of 2^63 panics OpenFile/OpenReaderEPSS —CVE-2026-107223HIGHExcelize: Unbounded <col max> attribute is loaded with no MaxColumns check and expanded per-column by flatCols(), so any column mutator hangs or OOMs the processEPSS —