CVE-2021-3672
No known exploitation. EPSS puts it in the 86th percentile. A vendor fix is available.
What to do
The vendor has published a fix. Version details are below where the sources state them.
What it is
From the CVE record
A flaw was found in c-ares library, where a missing input validation check of host names returned by DNS (Domain Name Servers) can lead to output of wrong hostnames which might potentially lead to Domain Hijacking. The highest threat from this vulnerability is to confidentiality and integrity as well as system availability.
In plain language
No plain-language summary for this CVE yet.
Exploitation
Where each signal puts this CVE on the scale from published to confirmed exploited.
- CISA KEV
Not in the catalog. CISA has not confirmed exploitation.
- Public exploits
No public exploit or proof of concept found in the sources we track.
- EPSS
2.8% chance of exploitation activity in the next 30 days, which ranks it in the 86th percentile of scored CVEs.
Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.
Lifecycle
6 events over 1675 days, from the signal feeds we watch.
- OpenVAS check added
- Patch availablerecord updated
- Publishedweakness classified, att&ck mapped
Affected products
- enterprise linux workstationOperating Systems / linux-distro
- enterprise linux computer nodeOperating Systems / linux-distro
- enterprise linux for ibm z systemsOperating Systems / linux-distro
- enterprise linux for ibm z systems eusOperating Systems / linux-distro
- enterprise linux for power little endianOperating Systems / linux-distro
- enterprise linux for power little endian eusOperating Systems / linux-distro
- enterprise linux server update services for sap solutionsOperating Systems / linux-distro
- enterprise linux tusOperating Systems / linux-distro
And 11 more affected products. See all after sign-in
Technical detail
CVSS 3.1 vector
Open in the CVSS calculatorCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L
Scored 5.6 by NVD.
How it is reached
- Attack Vector NetworkExploitable remotely over the network without any special conditions
- Attack Complexity HighRequires specific conditions like a race condition or non-default configuration
- Privileges Required NoneNo authentication required — anyone can exploit this
- User Interaction NoneNo user interaction needed — fully automated exploitation
Scope
- Scope UnchangedImpact is limited to the vulnerable component itself
Impact if exploited
- Confidentiality LowSome restricted information is disclosed, but limited in scope
- Integrity LowData modification is possible but limited in scope or consequence
- Availability LowReduced performance or intermittent disruption of service
Weaknesses
ATT&CK techniques
Mapped from the weaknesses above (CWE to ATT&CK), not observed in attacks.
Sources
References in the record
- c-ares.haxx.se/adv_20210810.html&
- nvd.nist.gov/vuln/detail/CVE-2021-3672&
- security-tracker.debian.org/tracker/CVE-2021-3672&
And 95 more references. See all after sign-in
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