CVE-2023-31039

Code execution via pid-file command substitution

Published May 8, 2023 · Updated Feb 13, 2025

Command injection in Apache bRPC before 1.5.0 allows attackers to execute code through a crafted ServerOptions::pid_file value. PutPidFileIfNeeded passes that value to wordexp with command expansion enabled before creating the PID file. Reachability requires control of the server startup configuration, and injected commands run with the bRPC process permissions.

CVSS severity9.8
Critical
EPSS probability1.52%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Command injection in Apache bRPC before 1.5.0 allows attackers to execute code through a crafted ServerOptions::pid_file value. PutPidFileIfNeeded passes that value to wordexp with command expansion enabled before creating the PID file. Reachability requires control of the server startup configuration, and injected commands run with the bRPC process permissions.

The record

CVE
CVE-2023-31039
Published
May 8, 2023
Updated
Feb 13, 2025
Vendor
The Apache Software Foundation
Product
Apache bRPC
Classifications
CWE-20, T1059.004
Attack vector
Unavailable
Privileges
Unavailable

Timeline

How it unfolded

  1. May 8, 2023CVE publishedPublication date reported by the CVE source.
  2. Feb 13, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0.9.0 <1.5.0

What conditions does exploitation require?

Attack vectorUnavailable in this record.
Required privilegesUnavailable in this record.

What is affected?

The Apache Software Foundation · Apache bRPCversion=0.9.0 <1.5.0

Published CVSS scores

9.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
9.8CISA-ADPCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
VectorUnavailable
PrivilegesUnavailable
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-20Improper Input Validation
T1059.004Unix Shell

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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