CVE-2026-78667
High
Description
When parsing a Range header containing a large number of small ranges, FileServer(FS), ServeContent, and ServeFile(FS) can consume an excessive amount of CPU.
SeverityHigh
CVSS7.5
Exploit probability—
Product
Stdlib
PublishedOct 8, 2026
First seenOct 8, 2026
Weakness typeCWE-770Allocation of resources without limits
How to fix
Update
- stdlib1.26.9, 1.27.2 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| stdlibGo | v < 1.26.9, 1.27.0-0 ≤ v < 1.27.2 | 1.26.9, 1.27.2 |
| microsoft azl3_golang_1.26.7-1 | No range specified | — |
| microsoft azl3_golang_1.27.1-1 | No range specified | — |
| microsoft azl3_golang_1.26.10-1 | No range specified | — |
| microsoft azl3_golang_1.27.3-1 | No range specified | — |
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