Description
tar.Reader can allocate an unbounded amount of memory when reading a maliciously-crafted archive containing a large number of sparse regions encoded in the "old GNU sparse map" format.
Affected products
golang: go
References4
- pkg.go.dev/vuln/GO-2026-4869 Vendor Advisory
- go.dev/cl/763766 Patch
- go.dev/issue/78301 Issue Tracking
- groups.google.com/g/golang-announce/c/0uYbvbPZRWU Mailing ListRelease Notes
Metrics
- CVSS 3.1
-
5.5
MEDIUM
Score source: NVD
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 0% percentile: 22 · as of 12 November 2026
- CWE
- CWE-770
Could this be exploited in your environment?
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