Security readout for executives and security teams
Plain-English summary
Arista's CloudVision eXchange (CVX) can crash when a connected switch sends unexpected TCP messages, destabilizing the CVX cluster and creating a denial-of-service condition. The attacker must already hold high-privilege access on a switch that talks to CVX, which limits who can trigger it but does not eliminate the operational risk to network management.
Executive priority
Priority: Elevated but not emergency. This flaw can knock the CVX network management fabric offline, disrupting visibility and automation, but exploitation requires a trusted switch to already be compromised. Schedule remediation in the next standard maintenance window and confirm privileged access controls on network devices are current.
Technical view
Per Arista's advisory, CVX does not validate or gracefully handle unexpected messages arriving from a connected switch, causing agent crashes that propagate into cluster instability. The weakness is classified as CWE-20 (Improper Input Validation) with CVSS 4.0 score 7.1 (AV:N/AC:L/PR:L/VA:H). Affected EOS/CVX trains listed include 4.34.0F, 4.33.0M, 4.32.0M, 4.31.0, and 4.30.0. Impact is limited to availability of the CVX control plane.
Likely exposure
Exposure is scoped to organizations running Arista CVX with switches connected to the CVX cluster. Because exploitation requires high-privilege access on a connected switch, the attack surface is primarily insider misuse or an adversary that has already compromised a managed switch. Internet-facing exposure is not indicated in the source bundle.
Exploitation context
No public exploitation, KEV listing, or proof-of-concept is cited in the source bundle. Arista's advisory describes the behavior as a DoS scenario reachable only from an already-privileged position on a connected switch. Treat as vendor-disclosed with no evidence of active abuse at time of publication.
Researcher notes
CWE-20 input-validation failure in CVX agent message handling; CVSS 4.0 vector confirms availability-only impact (VA:H, VC:N, VI:N) with low privileges from an adjacent trusted switch. Vendor advisory is the sole authoritative reference; no CPEs, patched versions, or workarounds are enumerated in the bundle beyond affected trains. Recommend pulling fixed-release data directly from Arista's advisory page and correlating with internal CVX telemetry for prior crash signatures.
Mitigation direction
- Review Arista Security Advisory 0126 and apply the vendor-recommended fixed EOS/CVX release train.
- Restrict and audit administrative access to switches permitted to communicate with CVX clusters.
- Segment the CVX management network so only trusted switches can reach CVX TCP services.
- Monitor CVX agent health and cluster state for crash loops or unexpected restarts.
- Enforce strong authentication and least-privilege on switch accounts capable of reaching CVX.
Validation and detection
- Inventory EOS/CVX versions and compare against 4.30.0, 4.31.0, 4.32.0M, 4.33.0M, and 4.34.0F trains listed in the advisory.
- Confirm which switches maintain TCP sessions to CVX and validate their administrative account hygiene.
- Check CVX agent logs and cluster telemetry for prior unexplained crashes or instability.
- Verify network ACLs restrict CVX-bound traffic to authorized switches and management sources.
- Track the Arista advisory page for updated fixed-version guidance and hotfix availability.
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-20: 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-2025-5090 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
- High
- CVSS
- 7.1 (4.0)
- Known Exploited
- No
- Published
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
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.
SSVC decision data
CVSS vector scores
2 official scoresWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N——AristaCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H2.83.6AristaVulnerability scoring details
Base CVSS 4.0 score
7.1HighVector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
Base CVSS 3.1 score
6.5MediumVector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Vulnerability timeline
Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.
- CVE reservedCVE Program
The CVE ID was reserved by the assigning CNA.
- CVE publishedCVE Program
The CVE record was published.
- CVE updatedCVE Program
The CVE record metadata indicates this as the latest update time.
ADP provider summaries
Source materials
- CVE List V5 sourceCVE List V5
- https://www.arista.com/en/support/advisories-notices/security-advisory/22868-security-advisory-0126CVE reference, Arista · vendor-advisory
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.
Improper Input Validation
Improper Input Validation represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.