CVE-2023-26562Network attack vector

Unauthorized email via missing account-status validation

Published Feb 13, 2024 · Updated Oct 28, 2024

Authorization bypass in Zimbra Collaboration 8.8.15 and 9.0 allows remote authenticated users to send email from closed accounts. The IMAP/SMTP mail-send path accepts a generated 2FA password without validating that the associated account status permits mail operations. Exploitation requires a closed account with 2FA and generated passwords configured for IMAP or SMTP, enabling unauthorized mail transmission under that account.

CVSS severity6.5
Medium
EPSS probability0.58%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Authorization bypass in Zimbra Collaboration 8.8.15 and 9.0 allows remote authenticated users to send email from closed accounts. The IMAP/SMTP mail-send path accepts a generated 2FA password without validating that the associated account status permits mail operations. Exploitation requires a closed account with 2FA and generated passwords configured for IMAP or SMTP, enabling unauthorized mail transmission under that account.

The record

CVE
CVE-2023-26562
Published
Feb 13, 2024
Updated
Oct 28, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-862, T1078
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Feb 13, 2024CVE publishedPublication date reported by the CVE source.
  2. Oct 28, 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?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

6.5CISA-ADPCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/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 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-862Missing Authorization
T1078Valid Accounts

Public exploit references

No public exploit references are available in this record.

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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