CVE-2026-39819: medium-severity vulnerability in Go toolchain cmd/go
Invoking "go bug" follows symlinks in predictable temporary filenames in cmd/go
Published · Updated
E-mail alert when it lands in KEV, gets a public PoC or its score goes up.
13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 5.3epss 0.2%
The "go bug" command writes to two files with predictable names in the system temporary directory (for example, "/tmp"). An attacker with access to the temporary directory can create a symlink in one of these names, causing "go bug" to overwrite the target of the symlink.
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:H/A:N
Affected products
Go toolchain · cmd/goRelated CVEs — Go toolchain cmd/go
In the same product, most dangerous first.
CVE-2020-28367—Arbitrary code execution via the go command with cgo in cmd/goEPSS 2.4%CVE-2020-28366—Arbitrary code execution in go command with cgo in cmd/go and cmd/cgoEPSS 2.3%CVE-2023-39323HIGHArbitrary code execution during build via line directives in cmd/goEPSS 1.9%CVE-2023-29404CRITICALImproper handling of non-optional LDFLAGS in go command with cgo in cmd/goEPSS 1.8%CVE-2023-39320—Arbitrary code execution via go.mod toolchain directive in cmd/goEPSS 1.8%CVE-2023-29405CRITICALImproper sanitization of LDFLAGS with embedded spaces in go command with cgo in cmd/goEPSS 1.7%