CVE-2026-73450
HIGH 7 ALL-YEARSOn affected platforms running Arista EOS with MLAG Dual Primary Detection configured, an unauthenticated attacker with access to the Dual Primary Detection network segment can send specially crafted packets to interfere with the dual-primary state. If the MLAG primary switch fails while these packets are present, the secondary switch incorrectly concludes it is in a dual-primary condition and err-disables its interfaces, leading to a traffic interruption.
Severe if exploited (CVSS 7), but no confirmed exploitation. Patch on a normal cadence.
Exploitation likelihood
0.2%chance of exploitation in 30 days · 5th percentile
Impact if exploited
7CVSS 4.0 · HIGH · CNA
- ConfidentialityNone
- IntegrityLow
- AvailabilityHigh
What an attacker needs
- ⚠Access: Must sit on the same / adjacent network
- ✓Privileges: No account or privileges required
- ✓User interaction: No user interaction needed
- ✓Complexity: No special conditions — reliably repeatable
- ⚠Requirements: Specific conditions must be present
✓ lowers the bar for an attacker · ⚠ raises it
Proof of concept & exploit code
No public exploit or proof-of-concept code is catalogued for this CVE (no ExploitDB, Nuclei, or CISA-KEV entry). It may still exist — search GitHub or check the references below.
Weakness (CWE)
- CWE-345: : Insufficient Verification of Data Authenticity
CVSS vector
CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:H
All CVSS metrics
- MEDIUM 6.9 v3.1 · CNA Primary
CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:C/C:N/I:L/A:H - HIGH 7 v4.0 · CNA Primary
CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:H - HIGH 7 v4.0 · NVD Secondary
CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - MEDIUM 6.9 v3.1 · NVD Secondary
CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:C/C:N/I:L/A:H