Is CVE-2026-82636 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-82636 being exploited in the wild.

How severe is CVE-2026-82636?

High severity, with a CVSS score of 7.9, published 30 August 2026.

Is there a fix for CVE-2026-82636?

A patch was published on 2026-08-28: qubes-core-dom0-linux version 4.3.22 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-82636 attacked?

It is attacked over the network, in an operating system.

Am I affected by CVE-2026-82636?

Check whether anything you run is named in the advisory. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-82636: Qubes OS command injection in qvm-copy-to-vm error handling

CVE-2026-82636 · Severity: high · CVSS 7.9 · Published 2026-08-30

Qubes OS uses qvm-copy-to-vm to securely copy files between the trusted Dom0 management domain and less-trusted virtual machines. A flaw in error message handling allows a compromised VM to inject shell commands that execute with Dom0 privileges, fully compromising the entire Qubes OS system. This affects any user who copies files from Dom0 to an untrusted VM.

Quick answers

Is CVE-2026-82636 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-82636 being exploited in the wild.
How severe is CVE-2026-82636?: High severity, with a CVSS score of 7.9, published 30 August 2026.
Which products and versions are affected?: Qubes OS before 4.3.22.
Is there a fix for CVE-2026-82636?: A patch was published on 2026-08-28: qubes-core-dom0-linux version 4.3.22 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-82636 attacked?: It is attacked over the network, in an operating system.
Am I affected by CVE-2026-82636?: Check whether anything you run is named in the advisory. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

The vulnerability is a command injection flaw in the qvm-copy-to-vm file transfer tool's error reporting mechanism. When file transfer fails, the target VM reports an error code and filename back to Dom0, which sanitizes only non-ASCII characters and quotes but leaves shell metacharacters intact. The Dom0 error handler then passes this unsanitized filename to system() call, which invokes a shell to display a dialog—allowing arbitrary command execution with Dom0 privileges. The attack requires an attacker to control a target VM that receives a copy request, but does not require prior compromise of Dom0 itself. The vulnerability affects all Qubes OS versions and is fixed in qubes-core-dom0-linux version 4.3.22 or later; the VM-side variant is unaffected because it uses execl() instead of system().

Affected products

Qubes OS before 4.3.22

Timeline

2026-08-29: disclosed
2026-08-28: patched: qubes-core-dom0-linux version 4.3.22

References

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