CVE-2011-2669Network attack vector

Browser crash via improper certificate validation

Published Jan 21, 2020 · Updated Aug 6, 2024

Improper certificate validation in Mozilla Firefox before 3.6 allows remote attackers to crash the browser via a crafted certificate. Public records do not identify the validation routine or explain which certificate property it handles incorrectly. A user must be induced to process the certificate; the documented consequence is an availability-only browser crash.

CVSS severity6.5
Medium
EPSS probability0.56%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper certificate validation in Mozilla Firefox before 3.6 allows remote attackers to crash the browser via a crafted certificate. Public records do not identify the validation routine or explain which certificate property it handles incorrectly. A user must be induced to process the certificate; the documented consequence is an availability-only browser crash.

The record

CVE
CVE-2011-2669
Published
Jan 21, 2020
Updated
Aug 6, 2024
Vendor
Mozilla
Product
Firefox
Classifications
CWE-295, T1499
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jan 21, 2020CVE publishedPublication date reported by the CVE source.
  2. Aug 6, 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=prior to 3.6

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Mozilla · Firefoxversion=prior to 3.6

Published CVSS scores

4.3NIST NVDAV:N/AC:M/Au:N/C:N/I:N/A:P
6.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

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-295Improper Certificate Validation
T1499Endpoint Denial of Service

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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