CVE-2026-126831
Awaiting Analysis
Awaiting Analysis - Queue
Heap-based Buffer Overflow in cpio via Long User/Group Names
Vulnerability report for CVE-2026-126831, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-11-12
Last updated on: 2026-11-12
Assigner: redhat-SADP
Description
Description
A flaw was found in cpio. A local user can cause a Denial of Service (DoS) by triggering a stack-based buffer overflow when creating archives in tar or ustar formats. When archiving files owned by users or groups with names exceeding 32 characters, cpio copies these names into fixed-size memory without verifying their length. This unbounded copy corrupts stack memory and causes the application to crash.
CVSS Scores
EPSS Scores
| Probability: | |
| Percentile: |
Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| Red Hat | Red Hat Enterprise Linux 10 | * |
| Red Hat | Red Hat Enterprise Linux 6 | * |
| Red Hat | Red Hat Enterprise Linux 7 | * |
| Red Hat | Red Hat Enterprise Linux 8 | * |
| Red Hat | Red Hat Enterprise Linux 9 | * |
| Red Hat | Red Hat Hardened Images | * |
Helpful Resources
Exploitability
CWE
KEV
| CWE ID | Description |
|---|---|
| CWE-121 | A stack-based buffer overflow condition is a condition where the buffer being overwritten is allocated on the stack (i.e., is a local variable or, rarely, a parameter to a function). |
