CVE-2026-66486: Improper Output Encoding in GNU cpio
CSIRTS triage
- What
- Improper output encoding in GNU cpio allows injection of unencoded output.
- Who is affected
- Systems using GNU cpio to extract and display archive contents.
- Urgency
- Unknown severity requires assessment; may allow code injection depending on context.
- Action
- Check GNU cpio project for security advisories and apply patches when released.
AI-assisted analysis generated from the source advisory — verify against the original.
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Details
Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-66486
Exploitation outlook
EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.
- Low exploitation riskCVE-2026-664860.14% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 3% of all EPSS-scored CVEs.
Referenced CVEs
| CVE | CSIRTS overview | External |
|---|---|---|
| CVE-2026-66486 | coverage & exploitation status | NVD · CVE.org |
Same CVEs, other sources
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