CVE-2026-45556
Roxy-WI: Authenticated arbitrary file write on every managed load balancer (and downstream RCE) via WAF rule save `config_file_name`
Description
Roxy-WI is a web interface for managing Haproxy, Nginx, Apache and Keepalived servers. In versions 8.2.6.4 and prior, POST /waf/<service>/<server_ip>/rule/<rule_id>/save accepts a config_file_name form field that is passed straight through to config_mod.master_slave_upload_and_restart(...) as the destination path. The validation chain (_replace_config_path_to_correct → check_is_conf) only requires the path to contain a hard-coded service substring (nginx/haproxy/apache2/httpd/keepalived) and the substring conf or cfg, and to not contain ... The encoded-slash substitution 92 → / is applied before the substring check, so the attacker can build any absolute path anywhere on the LB filesystem as long as it satisfies those substring constraints. The body of the WAF rule (config form field) is written verbatim to that path. By choosing a filename like 92etc92cron.d92nginx_cfg_evil (resolving to /etc/cron.d/nginx_cfg_evil), an attacker drops a cron entry on the load balancer with attacker-controlled content. Cron parses the file on its next scan, executing the embedded job as root — full RCE on every load balancer the caller's group manages. At time of publication, there are no publicly available patches.
INFO
Published Date :
June 10, 2026, 3:16 p.m.
Last Modified :
June 10, 2026, 3:16 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-45556
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | CRITICAL | [email protected] |
Solution
- Validate destination path against allowed locations.
- Sanitize user-supplied file names.
- Restrict write permissions for configuration files.
- Apply vendor patches when available.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-45556.
| URL | Resource |
|---|---|
| https://github.com/roxy-wi/roxy-wi/security/advisories/GHSA-85gm-773v-x7m4 |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-45556 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-45556
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-45556 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-45556 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by [email protected]
Jun. 10, 2026
Action Type Old Value New Value Added Description Roxy-WI is a web interface for managing Haproxy, Nginx, Apache and Keepalived servers. In versions 8.2.6.4 and prior, POST /waf/<service>/<server_ip>/rule/<rule_id>/save accepts a config_file_name form field that is passed straight through to config_mod.master_slave_upload_and_restart(...) as the destination path. The validation chain (_replace_config_path_to_correct → check_is_conf) only requires the path to contain a hard-coded service substring (nginx/haproxy/apache2/httpd/keepalived) and the substring conf or cfg, and to not contain ... The encoded-slash substitution 92 → / is applied before the substring check, so the attacker can build any absolute path anywhere on the LB filesystem as long as it satisfies those substring constraints. The body of the WAF rule (config form field) is written verbatim to that path. By choosing a filename like 92etc92cron.d92nginx_cfg_evil (resolving to /etc/cron.d/nginx_cfg_evil), an attacker drops a cron entry on the load balancer with attacker-controlled content. Cron parses the file on its next scan, executing the embedded job as root — full RCE on every load balancer the caller's group manages. At time of publication, there are no publicly available patches. Added CVSS V3.1 AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H Added CWE CWE-22 Added CWE CWE-20 Added CWE CWE-78 Added CWE CWE-73 Added Reference https://github.com/roxy-wi/roxy-wi/security/advisories/GHSA-85gm-773v-x7m4