CVE-2026-86334Public exploitNetwork attack vectorHinoki check available

Client file overwrite via image filename traversal

Published Sep 28, 2026 · Updated Sep 28, 2026

Path traversal in Canonical LXD lxc image export allows remote attackers to overwrite client files via a crafted image filename. The unified-image download path accepts a server-controlled Content-Disposition filename and joins it to the destination directory without removing traversal segments. Exploitation requires a user to export or copy an image from a malicious or intercepted server into a local directory; overwriting a startup file can lead to code execution as that user.

CVSS severity4.2
Medium
EPSS probability0.34%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Path traversal in Canonical LXD lxc image export allows remote attackers to overwrite client files via a crafted image filename. The unified-image download path accepts a server-controlled Content-Disposition filename and joins it to the destination directory without removing traversal segments. Exploitation requires a user to export or copy an image from a malicious or intercepted server into a local directory; overwriting a startup file can lead to code execution as that user.

The record

CVE
CVE-2026-86334
Published
Sep 28, 2026
Updated
Sep 28, 2026
Vendor
Canonical Ltd.
Product
LXD
Classifications
T1204
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 28, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 28, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

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

  1. Affected versionversion=4.0.2 <4.0.14
  2. Affected versionversion=5.0.0 <5.0.10
  3. Affected versionversion=5.21.0 <5.21.8
  4. Affected versionversion=6.0 <6.10

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Canonical Ltd. · LXDversion=4.0.2 <4.0.14; version=5.0.0 <5.0.10; version=5.21.0 <5.21.8; version=6.0 <6.10

Published CVSS scores

4.2Canonical GitHub Security AdvisoryCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:L/A:L

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Activity data is delayed. The latest report is Sep 28, 2026.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 22, 2026Sep 28, 2026
Latest reporting daySep 28, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

T1204User Execution

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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