CVE-2026-116775
Description
A flaw was found in pageant. A remote malicious server can trigger a Denial of Service (DoS) on a client system when SSH agent forwarding is bridged to a raw Pageant stream. By transmitting an excessively large frame length prefix, an attacker can force the client to buffer data without proper bounds checking, causing severe memory exhaustion and potential application termination.
Statement
This vulnerability is rated as Moderate severity because successful exploitation requires connecting to an untrusted or compromised SSH endpoint with agent forwarding routed to a Pageant transport, limiting the impact strictly to client-side memory exhaustion and application termination. It does not compromise confidentiality or integrity, nor does it allow arbitrary code execution. Furthermore, Pageant is a Windows-centric authentication agent mechanism, meaning native Red Hat enterprise environments do not deploy or expose this communication path in standard configurations.
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 | 6.5 | N/A | N/A |
| Attack Vector | Network | N/A | N/A |
| Attack Complexity | Low | 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 | None | N/A | N/A |
| Integrity Impact | None | N/A | N/A |
| Availability Impact | High | N/A | N/A |
Vector
Red Hat: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
Understanding the Weakness (CWE)
Availability
Technical Impact: DoS: Resource Consumption (CPU); DoS: Resource Consumption (Memory); DoS: Resource Consumption (Other)
When allocating resources without limits, an attacker could prevent other systems, applications, or processes from accessing the same type of resource. It can be easy for an attacker to consume many resources by rapidly making many requests or causing larger resources to be used than is needed.
Frequently Asked Questions
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