CVE-2023-6868Public exploitNetwork attack vector

Unauthorized WebPush messages via omitted VAPID key

Published Dec 19, 2023 · Updated Feb 13, 2025

Authorization bypass in Firefox for Android before 121 allows remote attackers to send empty WebPush messages without a valid VAPID key. WebPushEngineIntegration fails to pass the subscription's application-server key, causing Fenix to return an unsigned v1 endpoint instead of a VAPID-bound v2 endpoint. The attacker must obtain the private push endpoint and encryption keys; the demonstrated result is an unauthorized empty notification, not data disclosure or code execution.

CVSS severity4.3
Medium
EPSS probability0.49%
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 Firefox for Android before 121 allows remote attackers to send empty WebPush messages without a valid VAPID key. WebPushEngineIntegration fails to pass the subscription's application-server key, causing Fenix to return an unsigned v1 endpoint instead of a VAPID-bound v2 endpoint. The attacker must obtain the private push endpoint and encryption keys; the demonstrated result is an unauthorized empty notification, not data disclosure or code execution.

The record

CVE
CVE-2023-6868
Published
Dec 19, 2023
Updated
Feb 13, 2025
Vendor
Mozilla
Product
Firefox
Classifications
Unavailable
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Dec 19, 2023CVE publishedPublication date reported by the CVE source.
  2. Feb 13, 2025Record 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 <121

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Mozilla · Firefoxversion=unspecified <121

Published CVSS scores

4.3UbuntuCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/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.

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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 exploitPublished

Weakness, pattern, technique

No sourced classifications are available.

Public exploit references

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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