CVE-2026-66485

Process crash via archive-controlled stack allocation

Published Aug 10, 2026 · Updated Aug 10, 2026

Uncontrolled memory allocation in GNU cpio 2.15 and earlier allows attackers to crash the process via a crafted archive. During extraction, make_path in src/makepath.c passes an archive-controlled pathname length to alloca without bounding the resulting stack allocation. Exploitation requires the crafted archive to be extracted and interrupts only that cpio process; no confidentiality or integrity impact is reported.

CVSS severity4.6
Medium
EPSS probability0.13%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Uncontrolled memory allocation in GNU cpio 2.15 and earlier allows attackers to crash the process via a crafted archive. During extraction, make_path in src/makepath.c passes an archive-controlled pathname length to alloca without bounding the resulting stack allocation. Exploitation requires the crafted archive to be extracted and interrupts only that cpio process; no confidentiality or integrity impact is reported.

The record

CVE
CVE-2026-66485
Published
Aug 10, 2026
Updated
Aug 10, 2026
Vendor
The GnuPG Project
Product
GNU cpio
Classifications
CWE-789, T1499.004
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 10, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 10, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <=2.15

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

The GnuPG Project · GNU cpioversion=0 <=2.15

Published CVSS scores

4.6UbuntuCVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-789Memory Allocation with Excessive Size Value
T1499.004Endpoint Denial of Service: Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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