CVE-2026-47829: bosh-cli Argument Injection Leading to Local Command Execution

Technical summary

CVE-2026-47829 exploits insufficient input validation in bosh-cli's SSH command construction. When bosh-cli spawns SSH for non-interactive operations (remote command execution, log streaming), it does not properly sanitize OpenSSH arguments injected by a malicious BOSH Director. An attacker controlling the Director can craft responses that cause bosh-cli to pass attacker-controlled options to the local SSH binary. OpenSSH supports options like `-oProxyCommand=` and `-oLocalForward=` that enable arbitrary local command execution. The vulnerability exists in the argument-passing layer between bosh-cli and the system SSH process. Root cause is classified as CWE-88 (Argument Injection), indicating insufficient escaping or validation of untrusted input before constructing system commands.

Business impact

Operators managing Cloud Foundry deployments via BOSH are at direct risk of workstation compromise. If an operator's configured BOSH Director is compromised or an attacker gains network access to impersonate the Director, they gain the ability to execute commands with the operator's privileges on their local machine. This can lead to lateral movement within the operator's organization, theft of credentials, access to other infrastructure, and persistence mechanisms. The impact is amplified in environments where operators use shared or privileged credentials, or where workstations have access to sensitive systems (CI/CD, git repositories, production databases). Organizations should assess whether operators have recently connected to any BOSH Directors of unknown provenance.

Affected systems

bosh-cli versions prior to v7.10.4 are vulnerable. Organizations should audit deployments to identify which operator workstations are running affected versions. The vulnerability does not affect the BOSH Director server itself, nor does it require exploitation of the Director—rather, a compromised or untrusted Director becomes a vector for attacking operators' workstations. Any operator using bosh-cli to run remote commands or stream logs from a Director is potentially exposed.

Exploitability

Exploitation requires two conditions: (1) the operator must run a bosh-cli command that spawns SSH (bosh ssh -c, bosh logs -f, or similar non-interactive SSH operations), and (2) the target BOSH Director must be compromised or controlled by an attacker. The operator does not need to take any unusual action beyond normal BOSH operations; the attack is entirely driven by malicious responses from the Director. Once those conditions are met, arbitrary command execution on the operator's workstation follows reliably. No CISA KEV listing currently reflects known active exploitation, but the straightforward injection mechanism and high impact make this a priority target for attackers who gain Director access.

Remediation

Upgrade bosh-cli to version 7.10.4 or later. Organizations should identify all operator workstations running bosh-cli, verify their current versions, and prioritize upgrades in environments where BOSH Directors are accessible from less-trusted networks or where operators connect to multiple Directors. Additionally, apply zero-trust principles to BOSH Director infrastructure—ensure Director endpoints are authenticated and encrypted, and consider network segmentation to limit which workstations can reach Directors.

Patch guidance

Update bosh-cli to v7.10.4 or later. Verify the installed version on operator workstations by running `bosh --version`. Coordinate upgrades across the operator team, as multiple workstations may be affected. Review release notes for v7.10.4 to confirm the argument injection fix and check for any other relevant security improvements. Organizations using CI/CD pipelines or automation that invoke bosh-cli should also audit and upgrade those systems.

Detection guidance

Monitor for unexpected child processes spawned by the local SSH binary (`ssh` or `sshd`) on operator workstations, particularly those with suspicious command-line arguments or environment variables. Review SSH authentication logs for unusual activity or failed authentication attempts that may indicate exploitation attempts. On the BOSH Director side, log and alert on unusual responses or errors returned to bosh-cli clients, though detection is limited without client-side visibility. Endpoint detection and response (EDR) tools can flag suspicious SSH invocations with attacker-controlled options. Network monitoring of BOSH Director communications can identify unusual response patterns that may indicate an ongoing attack.

Why prioritize this

This vulnerability scores CVSS 7.8 (HIGH) due to the combination of high impact (command execution), low attack complexity, and lack of user interaction beyond normal operations. While it requires a compromised Director or network position, that attack surface exists in many enterprises. Operators who use bosh-cli are typically infrastructure personnel with elevated access, making their workstation compromise a high-risk event. Patch deployment should be urgent for any environment where BOSH Directors are accessible from networks with untrusted clients or where Director infrastructure has been under recent threat assessment.

Risk score, explained

CVSS 7.8 reflects: Attack Vector (Local—the operator must run bosh-cli locally), Attack Complexity (Low—straightforward injection), Privileges Required (None—standard operator permissions suffice), User Interaction (Required—operator must execute bosh-cli), Scope (Unchanged—impact is confined to the operator's workstation), and impact on Confidentiality, Integrity, and Availability (all High—arbitrary command execution). The 'Local' vector is slightly misleading in CVSS convention; the attack originates from a remote Directory but executes locally. The HIGH severity is appropriate because command execution on a privileged operator workstation has severe downstream consequences for infrastructure security.

Frequently asked questions