CVE-2026-39817medium

CVE-2026-39817: medium-severity vulnerability in Go toolchain cmd/go

Invoking "go tool pack" does not sanitize output paths in cmd/go

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13Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 5.9epss 0.2%
The "go tool pack" subcommand (usually used only by the compiler as an internal tool with known-good inputs) does not sanitize output filenames. Extracting a malicious archive file with the "pack" subcommand can write files to arbitrary locations on the filesystem.
CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:C/C:N/I:H/A:N
Affected products
Go toolchain · cmd/go
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