CVE-2023-39003Public exploit

Local file disclosure via temporary-file symlink

Published Aug 9, 2023 · Updated Jul 9, 2026

Improper temporary-file handling in OPNsense Community before 23.7 and Business before 23.4.2 allows local users to read root-only files. The Crash Reporter follows /tmp/PHP_errors.log without validating its underlying object, so a symlink redirects its privileged read to an attacker-chosen file. Exploitation requires a local account and the temporary path to be absent; the demonstrated consequence is disclosure of /etc/master.passwd.

CVSS severity7.5
High
EPSS probability0.79%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper temporary-file handling in OPNsense Community before 23.7 and Business before 23.4.2 allows local users to read root-only files. The Crash Reporter follows /tmp/PHP_errors.log without validating its underlying object, so a symlink redirects its privileged read to an attacker-chosen file. Exploitation requires a local account and the temporary path to be absent; the demonstrated consequence is disclosure of /etc/master.passwd.

The record

CVE
CVE-2023-39003
Published
Aug 9, 2023
Updated
Jul 9, 2026
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-732, T1005
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 9, 2023CVE publishedPublication date reported by the CVE source.
  2. Jul 9, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

7.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
4.4LogicalTrustCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N

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)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-732Incorrect Permission Assignment for Critical Resource
T1005Data from Local System

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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