CVE-2026-100395: lxc · Link Following
Affects lxcSource CVE Database V5
Not known to be exploited · CVSS 6.8 Medium.
Data as of 5 Nov 2026, 22:33 UTC
Thin evidence
One scorer or none| CNA (GitHub_M) | CVSS 4.0 | 6.8 |
|---|
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:H/VA:H/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 5 Nov 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 5 Nov 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| lxclxc | Affected
| Fixed in– |
AI-suggested
As a mitigation, use the LXC_CLONE_KEEPNAME flag during cloning to avoid the hostname update and prevent the vulnerable write operation. Avoid cloning containers from untrusted or attacker-controlled root filesystems. Since unprivileged cloning and independent cloning implementations are not affected, prefer those when possible.
Description
CVE-2026-100395 is a vulnerability in LXC version 7.0.0 and earlier where the lxc-copy tool and the liblxc clone() API can follow attacker-controlled symbolic links when updating /etc/hostname in a copied container root filesystem. This can lead to a privileged process overwriting files outside the intended container root filesystem if the source rootfs is attacker-controlled or less trusted. The issue arises because the clone operation preserves symlinks before updating the hostname, allowing a symlink to point outside the destination rootfs. Unprivileged users and independent cloning implementations are not affected. Using the LXC_CLONE_KEEPNAME flag avoids the hostname update and mitigates the issue.