Security readout for executives and security teams
Plain-English summary
CVE-2021-3468 is a local denial-of-service flaw in Avahi. A local attacker can make the Avahi service enter an infinite loop and become unresponsive. The impact is availability-focused, not data theft or remote takeover based on the supplied sources.
Executive priority
Treat this as a targeted availability risk. It is not shown as actively exploited or remotely reachable in the supplied evidence, but affected shared systems should be patched through normal security maintenance.
Technical view
Avahi versions 0.6 through 0.8 mishandle the client-connection termination event on the Avahi Unix socket in client_work. This maps to CWE-835, an infinite loop condition, allowing a local attacker to hang the Avahi service.
Likely exposure
Exposure is most likely on Linux or Unix systems running Avahi 0.6 through 0.8, particularly where local users or local processes can interact with the Avahi Unix socket.
Exploitation context
The source bundle supports local exploitation for service unresponsiveness. It does not show CISA KEV listing, active exploitation, remote exploitability, privilege escalation, or public exploit weaponization.
Researcher notes
Evidence is limited to the CVE description and vendor security references. The key condition is local interaction with the Avahi Unix socket causing client_work to loop indefinitely. Fixed version details are not provided in the bundle.
Mitigation direction
- Apply Avahi security updates from the relevant OS or distribution vendor.
- Check Red Hat, Debian, and other vendor guidance for fixed package status.
- Prioritize systems where Avahi availability supports discovery-dependent business workflows.
- Track unresolved systems as local denial-of-service exposure until patched.
Validation and detection
- Inventory installed Avahi package versions across Linux and Unix assets.
- Identify systems running Avahi versions 0.6 through 0.8.
- Verify whether vendor backported fixes are installed, not just upstream version strings.
- Confirm Avahi service health after applying the vendor update.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-835: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2021-3468 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Unknown
- CVSS
- Not scored
- Known Exploited
- No
- Published
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS and timeline data
No CVSS vectors or timeline events were available in the normalized CVE source material.
Source materials
- CVE List V5 sourceCVE List V5
- https://bugzilla.redhat.com/show_bug.cgi?id=1939614CVE reference · x_refsource_MISC
- [debian-lts-announce] 20220607 [SECURITY] [DLA 3047-1] avahi security updateCVE reference · mailing-list, x_refsource_MLIST
- https://lists.debian.org/debian-lts-announce/2023/06/msg00028.htmlCVE reference
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Loop with Unreachable Exit Condition ('Infinite Loop')
Loop with Unreachable Exit Condition ('Infinite Loop') represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.