CVE-2026-16461

Description

A stack-based buffer overflow was found in rpcbind's rpcinfo utility. In rpcbdump() short mode (used by rpcinfo -s), version numbers from a remote RPCBPROC_DUMP reply are written into a fixed-size stack buffer without bounds checking. A user or administrator who runs rpcinfo -s against a malicious or compromised rpcbind endpoint could experience a crash or denial of service of the rpcinfo client.

Statement

Moderate. This client-side vulnerability in the rpcinfo utility requires a user or administrator to execute rpcinfo -s against a malicious or compromised rpcbind endpoint. Exploitation can lead to a client crash and denial of service for the rpcinfo process.

Mitigation

To mitigate this issue, avoid using the `rpcinfo -s` command against untrusted, attacker-controlled, or compromised rpcbind hosts. Restrict the use of the rpcinfo utility to trusted internal endpoints or secure test environments only.

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 HatNVDcve.org
Base Score6.5N/A6.5
Attack VectorNetworkN/ANetwork
Attack ComplexityLowN/ALow
Privileges RequiredNoneN/ANone
User InteractionRequiredN/ARequired
ScopeUnchangedN/AUnchanged
ConfidentialityNoneN/ANone
Integrity ImpactNoneN/ANone
Availability ImpactHighN/AHigh

Vector

Red Hat: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

cve.org: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

Red Hat CVSS v3 Score Explanation

Inherited from the original combined report's assessment — same bug class as the sibling rpcbaddrlist() overflow (CVE-2026-16277): attacker-controlled rpcbind reply overflows a fixed stack buffer via unbounded sprintf(), causing a client-side crash. Not independently re-derived; revisit if further analysis changes the impact.

Understanding the Weakness (CWE)

Availability

Technical Impact: Modify Memory; DoS: Crash, Exit, or Restart; DoS: Resource Consumption (CPU); DoS: Resource Consumption (Memory)

Buffer overflows generally lead to crashes. Other attacks leading to lack of availability are possible, including putting the program into an infinite loop.

Integrity,Confidentiality,Availability,Access Control

Technical Impact: Modify Memory; Execute Unauthorized Code or Commands; Bypass Protection Mechanism

Buffer overflows often can be used to execute arbitrary code, which is usually outside the scope of a program's implicit security policy.

Integrity,Confidentiality,Availability,Access Control,Other

Technical Impact: Modify Memory; Execute Unauthorized Code or Commands; Bypass Protection Mechanism; Other

When the consequence is arbitrary code execution, this can often be used to subvert any other security service.

Acknowledgements

Red Hat would like to thank Aisle Research for reporting this issue.

Frequently Asked Questions

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