Vulnerability · CVE-2026-49238
An issue was discovered in Canonical Multipass before version 1.16.3.
Published May 28, 2026 · catalog updated Oct 14, 2026 · An issue was discovered
Check if you run it
No confirmed exploitation is on record for CVE-2026-49238. EPSS is 0.45%. Act only if a listed version of An issue was discovered is installed.
Gaps on this record
- The stored product name is a package slug. The name on this page is taken from the title (An issue was discovered).
- No version range is stored. A customer cannot check an installed version against this record.
- No vendor fix or required action is stored. Compare the linked advisory before you change production.
- Severity
- High8.4
- Known exploitation
- Not in CISA/VulnCheck KEV
- EPSS
- 0.45%
- Remediation
- Advisory link
- Affected products
- cpe canonical/multipass
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.
Are you affected?
Enter the version you run. The result uses only the ranges stored on this record.
The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.
- cpe canonical/multipassversion unspecified
How to fix CVE-2026-49238
Recommended remediation
A patch or advisory reference is linked. Open the original publisher for availability by product version.
Official advisories
What to do
Three questions, each answered from this record only. Confirm the vendor advisory before you patch.
Should you patch?
No confirmed exploitation is on record for CVE-2026-49238. EPSS is 0.45%. Act only if a listed version of An issue was discovered is installed.
Which versions are affected?
Affected version ranges are not on this record. Compare the installed version with the linked vendor advisory before you change production.
What should an analyst verify?
CWE-22: Path Traversal. EPSS 0.45%. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.
Technology hubs
Code
The project this record applies to. Exploit listings stay in References.
No public source repository is identified for this product.
Timeline
Detection, updates, and resolution for this record.
May 28, 2026 · NIST NVD
Detected
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
Oct 14, 2026 · NIST NVD
Updated
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
Sources
- CVE.orgVulnerability recordCVE-2026-49238
Official CVE identifier
cve.org - FIRST EPSSExploitation probabilityCVE-2026-49238
30-day exploitation probability 0.4%
first.org - NIST NVDVulnerability recordCVE-2026-49238
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_se
nvd.nist.gov
References
Freshness
Last verified in this catalog Oct 18, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.