CVE-2026-111749
Description
A flaw was found in aiohttp. When processing HTTP cookies, a response from an untrusted subdomain can remove the Host-Only attribute from an existing parent-domain cookie. This vulnerability allows an attacker controlling a subdomain to bypass domain isolation protections, potentially exposing sensitive host-specific cookies across broader domain scopes.
Statement
This vulnerability is rated as having a Moderate impact for Red Hat products because exploitation requires an aiohttp client session to interact with an untrusted subdomain while retaining a sensitive parent domain's cookie context. In standard Red Hat deployments, including OpenShift AI and Ansible Automation Platform, aiohttp operates primarily as an internal service connector querying predefined, trusted network endpoints. Because backend client sessions do not normally browse untrusted tenant subdomains or share session jars across untrusted domains, the practical risk to enterprise workloads is significantly reduced.
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 | 4.2 | N/A | N/A |
| Attack Vector | Network | N/A | N/A |
| Attack Complexity | High | N/A | N/A |
| Privileges Required | None | N/A | N/A |
| User Interaction | Required | N/A | N/A |
| Scope | Unchanged | N/A | N/A |
| Confidentiality | Low | N/A | N/A |
| Integrity Impact | Low | N/A | N/A |
| Availability Impact | None | N/A | N/A |
Vector
Red Hat: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N
Understanding the Weakness (CWE)
Access Control,Other
Technical Impact: Gain Privileges or Assume Identity; Varies by Context
An attacker can access any functionality that is inadvertently accessible to the source.
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