{"id":"CVE-2026-39817","aliases":["GO-2026-4979","BIT-golang-2026-39817"],"title":"Invoking \"go tool pack\" does not sanitize output paths in cmd/go","summary":"Invoking \"go tool pack\" does not sanitize output paths in cmd/go","severity":"medium","cvss":5.9,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:C/C:N/I:H/A:N","vendor":"toolchain","product":"toolchain","ecosystem":"go","affected":["toolchain >= 1.26.0-0, < 1.26.3"],"patched":["toolchain 1.26.3"],"published":"2026-05-07","updated":"2026-09-22","sourceUpdated":"2026-09-22T10:41:48.476924269Z","source":"OSV","sourceUrl":"https://osv.dev/vulnerability/GO-2026-4979","references":[{"url":"https://go.dev/issue/78778"},{"url":"https://go.dev/cl/767520"},{"url":"https://groups.google.com/g/golang-announce/c/qcCIEXso47M"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-39817.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-39817"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2467825"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-39817"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-39817"},{"url":"https://pkg.go.dev/vuln/GO-2026-4979"},{"url":"https://access.redhat.com/errata/RHSA-2026:49702"},{"url":"https://access.redhat.com/errata/RHSA-2026:22120"},{"url":"https://access.redhat.com/errata/RHSA-2026:22112"},{"url":"https://access.redhat.com/errata/RHSA-2026:61253"},{"url":"https://access.redhat.com/errata/RHSA-2026:57649"},{"url":"https://access.redhat.com/errata/RHSA-2026:49712"},{"url":"https://access.redhat.com/errata/RHSA-2026:22121"},{"url":"https://access.redhat.com/errata/RHSA-2026:43692"},{"url":"https://access.redhat.com/errata/RHSA-2026:62391"},{"url":"https://access.redhat.com/errata/RHSA-2026:66561"},{"url":"https://access.redhat.com/errata/RHSA-2026:57194"}],"tags":["osv","go","csaf","vex","red-hat"],"epss":0.0017,"epssPercentile":0.06342,"cvssSource":"vendor","cwe":["CWE-22"],"ingestedAt":"2026-08-26T19:27:02.399Z","slug":"CVE-2026-39817","body":"## Overview\n\nThe \"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.\n\n## Affected packages\n\n- `toolchain >= 1.26.0-0, < 1.26.3`\n\n## Remediation\n\nUpgrade to a patched release:\n\n- `toolchain 1.26.3`\n\n## Vendor advisories\n\n- **RHSA-2026:49702** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream EUS (v. 10.0) · released 2026-08-03 · [advisory](https://access.redhat.com/errata/RHSA-2026:49702)\n- **RHSA-2026:22120** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 10) · released 2026-06-01 · [advisory](https://access.redhat.com/errata/RHSA-2026:22120)\n- **RHSA-2026:22112** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 8) · released 2026-06-01 · [advisory](https://access.redhat.com/errata/RHSA-2026:22112)\n- **RHSA-2026:61253** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream E4S (v.9.2) · released 2026-08-31 · [advisory](https://access.redhat.com/errata/RHSA-2026:61253)\n- **RHSA-2026:57649** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream E4S (v.9.4) · released 2026-08-20 · [advisory](https://access.redhat.com/errata/RHSA-2026:57649)\n- **RHSA-2026:49712** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream EUS (v.9.6) · released 2026-08-03 · [advisory](https://access.redhat.com/errata/RHSA-2026:49712)\n- **RHSA-2026:22121** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 9) · released 2026-06-01 · [advisory](https://access.redhat.com/errata/RHSA-2026:22121)\n- **RHSA-2026:43692** · Red Hat · fixed in: OpenShift API for Data Protection 1.6 · released 2026-07-22 · [advisory](https://access.redhat.com/errata/RHSA-2026:43692)\n- **RHSA-2026:62391** · Red Hat · fixed in: Red Hat Hardened Images · released 2026-09-02 · [advisory](https://access.redhat.com/errata/RHSA-2026:62391)\n- **RHSA-2026:66561** · Red Hat · fixed in: Red Hat Hardened Images · released 2026-09-11 · [advisory](https://access.redhat.com/errata/RHSA-2026:66561)\n- **RHSA-2026:57194** · Red Hat · fixed in: multicluster engine for Kubernetes 2.11 · released 2026-08-19 · [advisory](https://access.redhat.com/errata/RHSA-2026:57194)\n- **Red Hat VEX** · Moderate · affected: Red Hat Hardened Images, Multicluster Engine for Kubernetes, Red Hat Advanced Cluster Management for Kubernetes 2, Red Hat OpenShift Container Platform 4 · no fix planned: Red Hat Hardened Images · updated 2026-09-21 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-39817.json)","depth":"sunlit","depthScore":32,"depthScoreParts":{"impact":32.5,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[{"seq":5146,"id":"CVE-2026-39817","ts":1788887250888,"field":"cvss","old":null,"new":"5.9"},{"seq":5145,"id":"CVE-2026-39817","ts":1788887250888,"field":"severity","old":"none","new":"medium"},{"seq":4029,"id":"CVE-2026-39817","ts":1788886366794,"field":"cvss","old":"5.9","new":null},{"seq":4028,"id":"CVE-2026-39817","ts":1788886366794,"field":"severity","old":"medium","new":"none"},{"seq":3161,"id":"CVE-2026-39817","ts":1788883133139,"field":"cvss","old":null,"new":"5.9"},{"seq":3160,"id":"CVE-2026-39817","ts":1788883133139,"field":"severity","old":"none","new":"medium"}]}