CVE-2026-79591
High
Description
A heap-buffer-overflow and use-after-free vulnerability exists in the xls_getCSS() function of libxls 1.6.3 due to insufficient validation of a file-controlled font index.
SeverityHigh
CVSS7.8
Exploit probability—
ProductLibxls
PublishedSep 10, 2026
First seenSep 10, 2026
Weakness typeCWE-122CWE-122
How to fix
Sources list no fixed version or patch link for this vulnerability.
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| libxls | 1.6.3 | — |
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