CVE-2026-16531

Description

An unauthenticated remote attacker can exploit a path traversal vulnerability in the PCP pmproxy logger servlet using a crafted hostname. This allows arbitrary file and directory creation, potentially leading to a denial of service.

Statement

Moderate: The pmproxy logger servlet in PCP is susceptible to a path traversal vulnerability, enabling an unauthenticated remote attacker to create arbitrary files and directories. This can lead to a denial of service or other impacts on systems where pmproxy is exposed on TCP port 44322, as the logger servlet is unconditionally active.

Mitigation

To mitigate this issue, restrict network access to TCP port 44322, which is used by the pmproxy service. This can be achieved by configuring a firewall to block incoming connections to this port. Alternatively, if the pmproxy service is not essential for your environment, it can be disabled.

To disable the pmproxy service:
sudo systemctl stop pmproxy
sudo systemctl disable pmproxy

Warning: Disabling pmproxy may impact the functionality of Performance Co-Pilot components that rely on it for data collection and logging.

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 Score5.3N/A5.3
Attack VectorNetworkN/ANetwork
Attack ComplexityLowN/ALow
Privileges RequiredNoneN/ANone
User InteractionNoneN/ANone
ScopeUnchangedN/AUnchanged
ConfidentialityNoneN/ANone
Integrity ImpactLowN/ALow
Availability ImpactNoneN/ANone

Vector

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

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

Understanding the Weakness (CWE)

Integrity,Confidentiality,Availability

Technical Impact: Execute Unauthorized Code or Commands

The attacker may be able to create or overwrite critical files that are used to execute code, such as programs or libraries.

Integrity

Technical Impact: Modify Files or Directories

The attacker may be able to overwrite or create critical files, such as programs, libraries, or important data. If the targeted file is used for a security mechanism, then the attacker may be able to bypass that mechanism. For example, appending a new account at the end of a password file may allow an attacker to bypass authentication.

Confidentiality

Technical Impact: Read Files or Directories

The attacker may be able read the contents of unexpected files and expose sensitive data. If the targeted file is used for a security mechanism, then the attacker may be able to bypass that mechanism. For example, by reading a password file, the attacker could conduct brute force password guessing attacks in order to break into an account on the system.

Availability

Technical Impact: DoS: Crash, Exit, or Restart

The attacker may be able to overwrite, delete, or corrupt unexpected critical files such as programs, libraries, or important data. This may prevent the product from working at all and in the case of protection mechanisms such as authentication, it has the potential to lock out product users.

Acknowledgements

Red Hat would like to thank Francisco Alisson Bezerra (TIM Security Red Team Research, TIM S.p.A), Lucas Gabriel Alves (TIM Security Red Team Research, TIM S.p.A), and Massimiliano Brolli (TIM Security Red Team Research, TIM S.p.A) for reporting this issue.

Frequently Asked Questions

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