CVE-2022-4066: A vulnerability was found in davidmoreno onion

Q: How do I fix CVE-2022-4066?

firefox: mitigate or apply the listed mitigation; onion: upgrade to 2022-09-05. Exact commands for each OS are on this page.

Q: Is CVE-2022-4066 being exploited?

CVE-2022-4066 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

Q: What does CVE-2022-4066 affect?

CVE-2022-4066 affects firefox, onion. Severity is low (CVSS 3.5). A vulnerability was found in davidmoreno onion. It has been rated as problematic. Affected by this issue is the function onion_response_flush of the file src/onion/response.c of the component Log Handler. The manipulation leads to allocatio

Q: How urgent is CVE-2022-4066?

Priority 34/100. Public exploit reference

Routine

LOW 3.5MITIGATEUPGRADE

CVE-2022-4066 is a low-severity flaw (CVSS 3.5) affecting firefox, onion. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

A vulnerability was found in davidmoreno onion. It has been rated as problematic. Affected by this issue is the function onion_response_flush of the file src/onion/response.c of the component Log Handler. The manipulation leads to allocation of resources. The name of the patch is de8ea938342b36c28024fd8393ebc27b8442a161. It is recommended to apply a patch to fix this issue. The identifier of this vulnerability is VDB-214028.

Why this priority

Public exploit reference

A fixed release or distro patch exists.

Risk facts

CVSS score	3.5 (Low)
Attack vector	Adjacent network
Attack complexity	Low
Privileges needed	Low
User interaction	None
EPSS exploit chance	1.2% (top 33%)
CISA exploited list	No
Weakness	CWE-404
Published	2022-11-19
Last modified	2026-06-17

Publisher (CNA): VulDB · Vendor: mozilla · onion project

Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2022-11-19 19:15 UTCPublished CVE record published
2026-06-17 05:19 UTCUpdated Record last modified

mozilla firefox MITIGATE

Affected: all versions

Fixed in: no fixed release known

Safe to downgrade to: no unaffected older release

1. Check installed version

apt-cache policy firefox || rpm -q firefox || firefox --version

No fixed or unaffected release known

Apply the vendor mitigation from the advisory, disable the affected feature, or restrict network access.

onion project onion UPGRADE

Affected: < 2022-09-05

Fixed in: 2022-09-05

Safe to downgrade to: no unaffected older release

1. Check installed version

apt-cache policy onion || rpm -q onion || onion --version

2. UPGRADE to 2022-09-05 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade onion

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade onion

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2022-4066?

firefox: mitigate or apply the listed mitigation; onion: upgrade to 2022-09-05. Exact commands for each OS are on this page.

Is CVE-2022-4066 being exploited?

CVE-2022-4066 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2022-4066 affect?

CVE-2022-4066 affects firefox, onion. Severity is low (CVSS 3.5). A vulnerability was found in davidmoreno onion. It has been rated as problematic. Affected by this issue is the function onion_response_flush of the file src/onion/response.c of the component Log Handler. The manipulation leads to allocatio

How urgent is CVE-2022-4066?

Priority 34/100. Public exploit reference

Software pages

Mozilla Firefox vulnerabilities

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References

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