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CVE-2026-55074NVD status: Deferred

ansible_jailexec: Improper Link Resolution Before File Access

CVE-2026-55074 is a high-severity improper link resolution before file access vulnerability in ansible_jailexec from Chofstede, with a CVSS 4.0 base score of 8.2 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected ansible_jailexec versions: < 2.0.0. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.44% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Check which version of ansible_jailexec you run against the affected versions below, and install the vendor's latest release.
  2. Read the advisory on github.com for workarounds and exact fixed builds.
  3. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
Chofstedeansible_jailexec< 2.0.0Not stated

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
HighSuccess depends on conditions outside the attacker's control.
Attack requirements
NoneThe attack does not depend on a particular deployment or configuration.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Confidentiality (vulnerable system)
NoneNo loss of confidentiality on the vulnerable system.
Integrity (vulnerable system)
HighSerious loss of integrity on the vulnerable system.
Availability (vulnerable system)
NoneNo loss of availability on the vulnerable system.
Confidentiality (other systems)
NoneNo loss of confidentiality on systems beyond the vulnerable one.
Integrity (other systems)
NoneNo loss of integrity on systems beyond the vulnerable one.
Availability (other systems)
NoneNo loss of availability on systems beyond the vulnerable one.

Vector: CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X. Scored by CNA (github.com).

Official description

Ansible FreeBSD Jail Connection Plugin is an Ansible connection plugin for FreeBSD Jails via jexec. Through version 1.3.0, the jailexec connection plugin's put_file resolved a transfer's destination to a path on the jail host ( + ) and ran mkdir -p and mv there as root on the host. Those commands follow symbolic links, and the path was operated on outside the jail, so a symlink existing inside the jail was followed by the host-side, root-privileged mv. A party controlling content inside a managed jail (the jail's root, or any process able to create a symlink in a directory an Ansible task later writes to) can therefore cause an arbitrary root-owned write on the host, outside the jail — a full jail escape. Arbitrary root-owned host writes are readily escalated to host compromise (e.g. cron, rc.d, authorized_keys). Preconditions for this vulnerability are that the operator runs a copy/template/fetch-style task (anything using put_file) against the jail, and the attacker can place a symlink inside the jail at or above the task's destination before the transfer runs. This issue has been fixed in version 2.0.0.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Improper Link Resolution Before File Access

The product attempts to access a file based on the filename, but it does not properly prevent that filename from identifying a link or shortcut that resolves to an unintended resource.

How developers prevent this class of flaw

  • Follow the principle of least privilege when assigning access rights to entities in a software system. Denying access to a file can prevent an attacker from replacing that file with a link to a sensitive file. Ensure good compartmentalization in the system to provide protected areas that can be trusted.

More Improper Link Resolution Before File Access vulnerabilities (CWE-59)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Recent Improper Link Resolution Before File Access vulnerabilities

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