CVE-2020-3812Public exploit

Local file-existence disclosure via privileged stat

Published May 26, 2020 · Updated Sep 16, 2024

Information disclosure in qmail-verify in Debian netqmail 1.06 allows local users to test arbitrary filesystem paths through crafted addresses. qmail-verify follows a user-controlled .qmail symlink and calls stat as root instead of adopting the account's UID and GID for the check. A local account and a running verification service are required; the response reveals only whether the referenced path exists, not its contents.

CVSS severity5.5
Medium
EPSS probability0.43%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Information disclosure in qmail-verify in Debian netqmail 1.06 allows local users to test arbitrary filesystem paths through crafted addresses. qmail-verify follows a user-controlled .qmail symlink and calls stat as root instead of adopting the account's UID and GID for the check. A local account and a running verification service are required; the response reveals only whether the referenced path exists, not its contents.

The record

CVE
CVE-2020-3812
Published
May 26, 2020
Updated
Sep 16, 2024
Vendor
Debian
Product
netqmail
Classifications
CWE-269, T1083
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. May 26, 2020CVE publishedPublication date reported by the CVE source.
  2. Sep 16, 2024Record 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=1.06

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Debian · netqmailversion=1.06

Published CVSS scores

2.1NIST NVDAV:L/AC:L/Au:N/C:P/I:N/A:N
5.5NIST NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

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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-269Improper Privilege Management
T1083File and Directory Discovery

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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