CVE-2026-94572
Description
A flaw was found in OpenStack Octavia. The tls_ciphers field on listeners and pools does not reject control characters or spaces. An authenticated project member can embed extra text in that field so that HAProxy treats it as additional configuration rather than a cipher list. This can change HAProxy behavior on the Amphora VM and, by injecting HAProxy program directives, can run commands on the Amphora. Only deployments that use the Amphora provider are affected.
Statement
This vulnerability is rated as Moderate. An authenticated project member can inject HAProxy configuration through the tls_ciphers field on a listener or pool of their own load balancer. On Red Hat OpenStack Platform Amphora images, SELinux enforcing prevents an injected program from executing, and HAProxy does not remain running with that configuration, so there is no confidentiality or integrity impact. The availability impact is Low because the disruption is limited to that tenant's load balancer and does not affect other tenants. It is not rated Important because the attacker cannot run commands as root and cannot reach other tenants' load balancers. Amphorae are single-tenant by design. Red Hat OpenStack Platform deployments that use the Amphora provider for Octavia are affected. Deployments that use the OVN provider are not affected because they do not generate HAProxy configuration files.
Mitigation
There is no complete mitigation for Amphora-based deployments other than restricting who can update listener and pool TLS settings. Operators can tighten Octavia policy.yaml so that os_load-balancer_api:pool:put and os_load-balancer_api:listener:put are limited to trusted roles. Deployments using the OVN provider instead of Amphora are not affected.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
The following CVSS metrics and score provided are preliminary and subject to review.
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 5 | N/A | N/A |
| Attack Vector | Network | N/A | N/A |
| Attack Complexity | Low | N/A | N/A |
| Privileges Required | Low | N/A | N/A |
| User Interaction | None | N/A | N/A |
| Scope | Changed | N/A | N/A |
| Confidentiality | None | N/A | N/A |
| Integrity Impact | None | N/A | N/A |
| Availability Impact | Low | N/A | N/A |
Vector
Red Hat: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:L
Red Hat CVSS v3 Score Explanation
RH CVSS 3.1 5.0 (Medium). Octavia maintainer confirmed on an enforcing Amphora that SELinux denies the injected program and HAProxy does not remain running, so confidentiality and integrity are None. Availability is Low because the disruption is limited to that tenant's load balancer. Scope stays Changed because the Octavia API and the Amphora are separate authorities.
Understanding the Weakness (CWE)
Access Control
Technical Impact: Bypass Protection Mechanism
In some cases, injectable code controls authentication; this may lead to a remote vulnerability.
Access Control
Technical Impact: Gain Privileges or Assume Identity
Injected code can access resources that the attacker is directly prevented from accessing.
Integrity,Confidentiality,Availability
Technical Impact: Execute Unauthorized Code or Commands
When a product allows a user's input to contain code syntax, it might be possible for an attacker to craft the code in such a way that it will alter the intended control flow of the product. As a result, code injection can often result in the execution of arbitrary code. Code injection attacks can also lead to loss of data integrity in nearly all cases, since the control-plane data injected is always incidental to data recall or writing.
Non-Repudiation
Technical Impact: Hide Activities
Often the actions performed by injected control code are unlogged.
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