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CVE-2026-26011: Opennav Nav2 Heap Buffer Overflow (CVSS 9.3)

CVE-2026-26011 is a critical severity heap buffer overflow in Opennav Nav2 with a CVSS score of 9.3. Apply the vendor fix and confirm exposure on internet facing and business critical assets first.

Last updated: Jun 17, 2026

Quick answer

Direct answer

CVE-2026-26011 is a critical severity heap buffer overflow in Opennav Nav2 with a CVSS score of 9.3. Apply the vendor fix and confirm exposure on internet facing and business critical assets first.

Risk scores

CVSS base score
9.3CRITICAL
EPSS probability
0.83%
Higher than 57 percent of all CVEs
CISA KEV
Not listed
CVSS metricWhat it means
Attack vector (AV:N)Network: reachable remotely
Attack complexity (AC:L)Low complexity
Attack requirements (AT:N)No attack requirements
Privileges required (PR:N)No privileges required
User interaction (UI:N)No user interaction
Confidentiality (VC:H)High confidentiality impact
Integrity (VI:H)High integrity impact
Availability (VA:H)High availability impact

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/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

About Opennav Nav2

CVE-2026-26011 affects Opennav Nav2, a product from Opennav. Before acting, confirm where Opennav Nav2 runs in your estate, who owns it and whether it is reachable from the internet, because exposure decides real risk more than the score alone.

What the flaw is

In plain terms: navigation2 is a ROS 2 Navigation Framework and System. In 1.3.11 and earlier, a critical heap out-of-bounds write vulnerability exists in Nav2 AMCL's particle filter clustering logic. By publishing a single crafted geometry_msgs/PoseWithCovarianceStamped message with extreme covariance values to the /initialpose topic, an unauthenticated attacker on the same ROS 2 DDS domain can trigger a negative index write (set->clusters[-1]) into heap memory preceding the allocated buffer. In Release builds, the sole boundary check (assert) is compiled out, leaving zero runtime protection. This primitive allows controlled corruption of the heap chunk metadata(at least the size of the heap chunk where the set->clusters is in is controllable by the attacker), potentially leading to further exploitation. At minimum, it provides a reliable single-packet denial of service that kills localization and halts all navigation.

The weakness class is Heap Buffer Overflow. A write past the end of a heap buffer corrupts nearby memory.

Based on its CVSS vector, the flaw can be reached over the network, needs no login, and needs no user interaction. Apply the vendor fix and confirm exposure on internet facing and business critical assets first.

Affected versions and timeline

FieldDetail
ProductOpennav Nav2
Affected versionsNav2 up to and including 1.3.11
PublishedFeb 12, 2026
Last modifiedJun 17, 2026
Added to CISA KEVNot listed
Assigning CNAsecurity-advisories@github.com

How to detect it

  • Inventory every instance of Opennav Nav2 and record the running version against the affected range above.
  • Check external attack surface scans for internet facing instances of the component.
  • Review logs on affected systems for unusual requests, errors or new processes around the vulnerable function.
  • Confirm with an authenticated vulnerability scan once your scanner has a check for this CVE.

How to fix it

  • Apply the fixed version of Opennav Nav2 named in the vendor advisory.
  • If patching must wait, restrict network access to the affected service and put it behind authentication or a web application firewall rule.
  • Rescan after the change to prove the exposure is gone, then close the ticket.

CTEM action plan

CTEM stageWhat to do for this CVE
ScopeAdd every business service that depends on Opennav Nav2 to the current CTEM cycle.
DiscoverFind all instances, including shadow and cloud deployments, and record versions and exposure.
PrioritizeRank using EPSS and CVSS together with asset exposure and business impact.
ValidateConfirm the flaw is reachable and exploitable in your environment and that compensating controls work.
MobilizeAssign the fix to the asset owner with a due date matched to the priority, then verify closure.

CWE References

Technical References

Frequently asked questions

CVE-2026-26011 is a critical severity heap buffer overflow in Opennav Nav2 with a CVSS score of 9.3. Apply the vendor fix and confirm exposure on internet facing and business critical assets first.

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