CVE-2026-45711Public exploitNetwork attack vector

Arbitrary file write via unchecked message IDs

Published Jul 20, 2026 · Updated Jul 20, 2026

Path traversal in Mailpit before 1.30.0 allows remote attackers to write files outside a dump directory through a malicious server. The dump --http code joins each untrusted response ID to the output path with path.Join, which normalizes traversal segments without checking containment. Exploitation requires a user to run the dump command against an attacker-controlled or intercepted endpoint; writes retain an .eml suffix and the user's filesystem privileges.

CVSS severity5.9
Medium
EPSS probability0.31%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Path traversal in Mailpit before 1.30.0 allows remote attackers to write files outside a dump directory through a malicious server. The dump --http code joins each untrusted response ID to the output path with path.Join, which normalizes traversal segments without checking containment. Exploitation requires a user to run the dump command against an attacker-controlled or intercepted endpoint; writes retain an .eml suffix and the user's filesystem privileges.

The record

CVE
CVE-2026-45711
Published
Jul 20, 2026
Updated
Jul 20, 2026
Vendor
Axllent
Product
Mailpit
Classifications
CWE-829, CWE-22, T1105
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jul 20, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 20, 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?

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

  1. Affected versionversion=< 1.30.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Axllent · Mailpitversion=< 1.30.0

Published CVSS scores

5.9GitHub, Inc.CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:H/A:L
8.2NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:L

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)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-829Inclusion of Functionality from Untrusted Control Sphere
CWE-22Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
T1105Ingress Tool Transfer

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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