SFTP Server VM Escape in Canonical Multipass
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | ||||||
|---|---|---|---|---|---|---|---|---|---|
| Canonical | Multipass | unaffected |
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No data.
| Vendor | Product | Versions | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Canonical | Multipass |
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No CVSS v4.0
No CVSS v3.0
No CVSS v2
This CVE is not in the KEV list.
Exploit prediction score: < 1% (0.505% probability within 30 days)
| Type | Values Removed | Values Added |
|---|---|---|
| CPEs | cpe:2.3:a:canonical:multipass:*:*:*:*:*:*:*:* |
| Type | Values Removed | Values Added |
|---|---|---|
| First Time appeared |
Canonical
Canonical multipass |
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| Vendors & Products |
Canonical
Canonical multipass |
| Type | Values Removed | Values Added |
|---|---|---|
| Metrics |
ssvc
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| Type | Values Removed | Values Added |
|---|---|---|
| Description | An issue was discovered in Canonical Multipass before version 1.16.3. The host-side SFTP server component (sshfs_server), which executes with root privileges on the host, contains a path containment bypass vulnerability within its validate_path function in src/sshfs_mount/sftp_server.cpp. The function performs a plain string prefix comparison on requested paths without path separator validation or dot-dot (..) normalization. A local attacker with root privileges inside a guest virtual machine can bypass the FUSE layer by injecting raw SFTP frames (such as an SSH_FXP_OPEN request) directly into the sshfs_server process stdin/stdout pipes via procfs. By supplying a path containing directory traversal sequences that match the allowed mount prefix, the attacker can force the host-side root process to resolve the traversal and open files outside the designated mount boundary. This allows a guest-side user to read arbitrary files on the host filesystem, resulting in a virtual machine escape. | |
| Title | SFTP Server VM Escape in Canonical Multipass | |
| Weaknesses | CWE-22 | |
| References |
| |
| Metrics |
cvssV3_1
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