CVE-2026-115378 lxc CVE debrief

Who should care

Operators and administrators of Incus deployments, especially those with untrusted or internet-accessible virtual machines, should assess their exposure and take necessary remediation steps. This includes verifying the version of Incus in use and upgrading to a patched version if necessary. Additionally, system administrators and security teams responsible for managing and securing system containers should be aware of this vulnerability and its potential impact on their systems.

Why it matters

CVE-2026-115378 is a medium-severity vulnerability in Incus that allows a malicious incus-agent to write arbitrary files on the host system during a recursive file pull operation. This could lead to privilege escalation and potential system compromise. Operators of Incus deployments should verify their inventory, restrict access to incus-agent, and upgrade to patched versions to mitigate this vulnerability.

• Verification of Incus version and exposure is required to determine if systems are vulnerable.
• Potential for attackers to write arbitrary files, such as /etc/shadow, could lead to privilege escalation.
• Successful exploitation could allow an attacker to escape the virtual machine and gain access to the host system.
• Remediation requires upgrading to patched versions of Incus (6.0.7, 7.0.2, or 7.5.0) and restricting access to incus-agent.

Technical summary

The Incus application, used for managing system containers, contains an arbitrary file write vulnerability in versions before 6.0.7, 6.1.0 before 7.0.2, and 7.1.0 before 7.5.0. This vulnerability, tracked as CVE-2026-115378, is exploitable through the sftpRecursivePullFile function during the execution of the incus file pull -r command. A malicious incus-agent can manipulate the file pull operation to escape the target directory, allowing the writing of attacker-controlled files on the host system, potentially leading to privilege escalation.

Defensive priority

Operators of Incus deployments should prioritize verification of their inventory and upgrade to patched versions, focusing on systems with untrusted or internet-accessible virtual machines.

Recommended defensive actions

• Verify Incus deployments for version exposure and upgrade to patched versions (6.0.7, 7.0.2, or 7.5.0) where necessary.
• Restrict access to incus-agent and limit its privileges to prevent potential exploitation.
• Monitor Incus deployments for suspicious activity, especially in environments with untrusted or internet-accessible virtual machines.
• Implement compensating controls, such as file system access controls and monitoring, to limit potential damage.
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up.
• Review the supplied official advisory or CVE record to validate affected scope, severity, and vendor guidance.
• Plan vendor-supported updates or mitigations through normal change control where exposure is confirmed.

Evidence notes

The CVE record and source item detail an arbitrary file write vulnerability in Incus versions before 6.0.7, 6.1.0 before 7.0.2, and 7.1.0 before 7.5.0, which allows a malicious incus-agent to escape the target directory during incus file pull -r, potentially writing attacker-controlled files such as /etc/shadow on the operator's host.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.