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CVE-2026-66486

Improper Output Encoding in GNU cpio

CVSS score

4.6

EPSS probability

%0.2

Risk score

0.0

Published

2 mo ago

A patch is available only for some products or versions

Kanıt listesindeki ürün ve sürüm eşleşmesini kontrol edin; bazı varyantlar hâlâ etkileniyor olabilir.

Impact on My Inventory

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Vulnerability description

DayBreach CVE AI Research

CVE-2026-66486 has vendor, distribution, patch and security-source records on file. We can compare them and prepare an explanation linked to the evidence.

GNU cpio is vulnerable to improper encoding or escaping of output in its archive member listing functionality. When listing archive members via cpio -it, member names are printed directly to output without quoting or escaping. An attacker can craft a cpio archive containing member names with embedded newline characters or ANSI escape sequences, causing forged listing entries or terminal control sequence injection when the listing is displayed. This issue has been fixed in commit 2ff9600c9ef32e88759843cdbde74c8db5ae9b30

IMPACT: Affected Products and Software

Affected Products

The following products are affected by CVE-2026-66486 vulnerability. Where our threat engine knows the exact affected versions, they are listed below.

IDVENDORPRODUCTACTION
1gnucpio View
2debiancpio (sid) View
3debiancpio (forky) View
4debiancpio (trixie) View
5debiancpio (bookworm) View
6debiancpio (bullseye) View
Total affected vendors: 2|Products: 6

RED HAT CSAF/VEX: Product Impact Check

Red Hat has not yet published a CSAF/VEX impact record for this CVE. This does not mean “not affected”.

SCORING: CVSS from Multiple Sources

CVSS Scores

The Common Vulnerability Scoring System is a standardised framework for assessing the severity of vulnerabilities in software and systems. We collect and display CVSS scores from several sources for each CVE.

SCOREVERSIONSEVERITYVECTORSOURCE
4.6CVSS V4_0MEDIUMCVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:L/VA:N/SC:N/SI:N/SA:NCVE CNA
4.6CVSS V40MEDIUMCVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:XNVD

Patch and Remediation Guide

Solution & Remediation Advisory

Partial patch

1 düzeltme kanıtı bulundu; en az 5 ürün veya sürüm hâlâ etkileniyor ya da inceleniyor.

reference

Yama veya çözüm referansı

Open source
Confirm the affected product and version against the source evidence above.
Restrict access to internet-facing services and apply network segmentation.
Apply the official update named in the evidence only to the matching product and version.
Monitor server logs and network endpoints for signs of anomalous execution.

Public exploit and active exploitation status

Verified exploit intelligence

No verified public PoC, exploit repository or Metasploit module has been found for this CVE yet.

Weakness Classification and Attack Patterns (CWE & CAPEC)

CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorises the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-66486 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-66486 weaknesses.

Attack Vector and Accessibility

ExposureYerel erişim
PermissionsGerekmiyor
User—

Official Sources and Advisories

CVSS Vector Radar Chart

4.6 / 10
Attack VectorLocalComplexityLowPrivilegesNoneUser Interact.RequiredConfidentialityLowIntegrityNoneAvailabilityNone

Vulnerability Scoring Details

CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N
Attack VectorLocal
Attack ComplexityLow
Privileges RequiredNone required
User InteractionA
Confidentiality (Gizlilik)Low
Integrity (Bütünlük)A
Availability (Erişilebilirlik)None

Kısmi yama

1 düzeltme kanıtı bulundu; en az 5 ürün veya sürüm hâlâ etkileniyor ya da inceleniyor.

Follow the vendor

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D
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debian

Weakness Type (CWE & CAPEC)

Similar Vulnerabilities

Get this vulnerability through the API

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