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CVE-2026-3893 Carlson Software CVE debrief

CVE-2026-3893 is a critical authentication failure in the Carlson Software VASCO-B GNSS Receiver <1.4.0. According to the CISA advisory, the device lacks an authentication mechanism, so an attacker with network access can directly access and modify configuration and operational functions without credentials. Carlson Software recommends updating to Version 1.4.0 or later.

Vendor
Carlson Software
Product
VASCO-B GNSS Receiver
CVSS
CRITICAL 9.4
CISA KEV
Not listed in stored evidence
Original CVE published
2026-04-23
Original CVE updated
2026-04-23
Advisory published
2026-04-23
Advisory updated
2026-04-23

Who should care

Organizations that deploy or manage Carlson VASCO-B GNSS receivers, along with OT/ICS security teams responsible for network segmentation, device hardening, and change control, should treat this as a high-priority issue. Any environment where the receiver is reachable from a broader network should be reviewed first.

Technical summary

The advisory describes a network-reachable missing-authentication condition on the Carlson VASCO-B GNSS Receiver <1.4.0. Because no authentication is required, an attacker with network access may alter configuration and operational behavior directly. The advisory lists CVSS v3.1 9.4 (AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:H) and recommends upgrading to version 1.4.0 or greater.

Defensive priority

High. This is an unauthenticated network-access issue affecting operational technology equipment, with potential integrity and availability impact. If the receiver is exposed to untrusted or shared networks, remediation should be prioritized immediately.

Recommended defensive actions

  • Upgrade Carlson VASCO-B GNSS Receiver to version 1.4.0 or greater per the vendor recommendation.
  • Restrict network access to the receiver so only necessary management hosts and segments can reach it.
  • Review device configuration and access paths for any unexpected changes or unauthorized operational modifications.
  • Apply OT network segmentation and defense-in-depth controls around the receiver and its management interfaces.
  • Validate whether any compensating controls are in place where immediate upgrading is not yet possible.

Evidence notes

The source advisory (ICSA-26-113-02) states that the Carlson VASCO-B GNSS Receiver lacks an authentication mechanism and that a network attacker can access and modify configuration and operational functions without credentials. The advisory was initially published on 2026-04-23T06:00:00Z. The provided source corpus includes no KEV listing for this CVE.

Sources and references

Verified primary and authoritative sources

  • CVE-2026-3893 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-3893

    CVE Program - Official CVE Program record with source-provided CVE metadata.

  • CVE-2026-3893 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-3893

    NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.

Supplemental references

  • Source item URL

    Unverified legacy reference

    URL: https://raw.githubusercontent.com/cisagov/CSAF/develop/csaf_files/OT/white/2026/icsa-26-113-02.json

    cisa_csaf

  • Source reference

    Unverified legacy reference

    URL: https://www.cisa.gov/news-events/ics-advisories/icsa-26-113-02

    Reference

  • Source reference

    Unverified legacy reference

    URL: https://www.cisa.gov/uscert/ics/alerts/ICS-ALERT-10-301-01

    Reference

  • Source reference

    Unverified legacy reference

    URL: https://www.cisa.gov/resources-tools/resources/ics-recommended-practices

    Reference

  • Source reference

    Unverified legacy reference

    URL: https://www.cisa.gov/sites/default/files/publications/Cybersecurity_Best_Practices_for_Industrial_Control_Systems.pdf

    Reference

  • Source reference

    Unverified legacy reference

    URL: https://www.cisa.gov/topics/industrial-control-systems

    Reference

  • Source reference

    Unverified legacy reference

    URL: https://www.cisa.gov/news-events/ics-alerts/ics-alert-10-301-01

    Reference

  • Source reference

    Unverified legacy reference

    URL: https://www.cisa.gov/sites/default/files/recommended_practices/NCCIC_ICS-CERT_Defense_in_Depth_2016_S508C.pdf

    Reference

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.