CVE-2012-1326Network attack vector

MITM attacks via unchecked intermediate CA constraints

Published Jan 15, 2020 · Updated Nov 15, 2024

Certificate-validation bypass in Cisco IronPort Web Security Appliance 7.5 and earlier allows remote attackers to perform MITM attacks. The HTTPS proxy accepts an intermediate certificate as a CA without checking its X.509 basic constraints, then re-signs the server certificate under its trusted proxy CA. An attacker who can present a crafted chain to proxied HTTPS traffic can spoof and intercept that traffic outside the proxy.

CVSS severity7.4
High
EPSS probability0.66%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Certificate-validation bypass in Cisco IronPort Web Security Appliance 7.5 and earlier allows remote attackers to perform MITM attacks. The HTTPS proxy accepts an intermediate certificate as a CA without checking its X.509 basic constraints, then re-signs the server certificate under its trusted proxy CA. An attacker who can present a crafted chain to proxied HTTPS traffic can spoof and intercept that traffic outside the proxy.

The record

CVE
CVE-2012-1326
Published
Jan 15, 2020
Updated
Nov 15, 2024
Vendor
ClamAV
Product
Cisco Secure Web Appliance
Classifications
CWE-20, T1557
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jan 15, 2020CVE publishedPublication date reported by the CVE source.
  2. Nov 15, 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=<= 7.5

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

ClamAV · Cisco Secure Web Applianceversion=<= 7.5

Published CVSS scores

5.8NIST NVDAV:N/AC:M/Au:N/C:P/I:P/A:N
7.4NIST NVDCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/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 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 exploitUnconfirmed

Weakness, pattern, technique

CWE-20Improper Input Validation
T1557Adversary-in-the-Middle

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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