CVE-2026-0883Network attack vector

Unauthenticated disclosure of unspecified networking data

Published Jan 13, 2026 · Updated Jan 13, 2026

Information disclosure in Mozilla Firefox before 147 and Firefox ESR before 140.7 allows remote attackers to read unspecified data. Mozilla identifies the Networking component but has not published the affected code locus, the operation that exposes data, or the data involved. The issue is reachable over a network without privileges or user interaction, and its reported impact is limited to confidentiality.

CVSS severity5.3
Medium
EPSS probability0.47%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Information disclosure in Mozilla Firefox before 147 and Firefox ESR before 140.7 allows remote attackers to read unspecified data. Mozilla identifies the Networking component but has not published the affected code locus, the operation that exposes data, or the data involved. The issue is reachable over a network without privileges or user interaction, and its reported impact is limited to confidentiality.

The record

CVE
CVE-2026-0883
Published
Jan 13, 2026
Updated
Jan 13, 2026
Vendor
Mozilla
Product
Firefox
Classifications
CWE-200
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jan 13, 2026CVE publishedPublication date reported by the CVE source.
  2. Jan 13, 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=unspecified <147

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Mozilla · Firefoxversion=unspecified <147
Mozilla · Firefox ESRversion=unspecified <140.7

Published CVSS scores

5.3CISA-ADPCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/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
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-200Exposure of Sensitive Information to an Unauthorized Actor

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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