CVE-2023-26434Network attack vector

Service interruption via unbounded POP3 capability responses

Published Jun 20, 2023 · Updated Aug 2, 2024

Uncontrolled resource consumption in OX App Suite backend 7.10.6-rev39 and earlier allows remote authenticated users to interrupt service. When an external POP3 account is added, the backend accepts capability responses without a plausible size limit and consumes excessive memory processing them. Exploitation requires an authenticated user to configure an account that reaches an attacker-controlled POP3 service; resource exhaustion makes the suite unavailable.

CVSS severity4.3
Medium
EPSS probability1.15%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Uncontrolled resource consumption in OX App Suite backend 7.10.6-rev39 and earlier allows remote authenticated users to interrupt service. When an external POP3 account is added, the backend accepts capability responses without a plausible size limit and consumes excessive memory processing them. Exploitation requires an authenticated user to configure an account that reaches an attacker-controlled POP3 service; resource exhaustion makes the suite unavailable.

The record

CVE
CVE-2023-26434
Published
Jun 20, 2023
Updated
Aug 2, 2024
Vendor
Open-Xchange GmbH
Product
OX App Suite
Classifications
CWE-400, T1499.004
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jun 20, 2023CVE publishedPublication date reported by the CVE source.
  2. Aug 2, 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=0 <=7.10.6-rev39

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Open-Xchange GmbH · OX App Suiteversion=0 <=7.10.6-rev39

Published CVSS scores

4.3Open-Xchange GmbHCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/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.

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-400Uncontrolled Resource Consumption
T1499.004Application or System Exploitation

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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