LiveActive security incident?Get immediate response
CVE Record

CVE-2026-22997: net: can: j1939: j1939_xtp_rx_rts_session_active(): deactivate session upon receiving the second rts

In the Linux kernel, the following vulnerability has been resolved: net: can: j1939: j1939_xtp_rx_rts_session_active(): deactivate session upon receiving the second rts Since j1939_session_deactivate_activate_next() in j1939_tp_rxtimer() is called only when the timer is enabled, we need to call j1939_session_deactivate_activate_next() if we cancelled the timer. Otherwise, refcount for j1939_session leaks, which will later appear as | unregister_netdevice: waiting for vcan0 to become free. Usage count = 2. problem.

HighCVSS 7.5Not KEV-listedUpdated
Discuss exposureBack to CVEs
Glexia's TakeAutomated analysishigh

Security readout for executives and security teams

Plain-English summary

CVE-2026-22997 is a Linux kernel availability flaw in the CAN J1939 networking code. A protocol session can be left referenced after a second RTS condition, causing cleanup problems and potential denial of service. This matters most for Linux systems that actually use CAN/J1939, common in embedded, industrial, and vehicle-adjacent environments.

Executive priority

Treat as high priority for fleets using Linux CAN/J1939, especially operational technology, embedded, automotive, or lab systems. For standard enterprise servers without CAN/J1939 use, urgency is lower but still belongs in the normal kernel patch cycle.

Technical view

The flaw is in j1939_xtp_rx_rts_session_active(). When an RTS is received for an active J1939 transport session and a timer is cancelled, the session deactivation path may not run. The source describes a leaked j1939_session refcount that later appears as unregister_netdevice waiting for vcan0 to become free.

Likely exposure

Exposure is likely limited to Linux hosts or devices running affected kernel versions with CAN J1939 functionality enabled or reachable. Typical internet-facing servers are less likely to be exposed unless they bridge or expose this protocol path. Distribution-specific kernel backports are not identified in the bundle.

Exploitation context

The bundle does not show CISA KEV listing or active exploitation. It supports a denial-of-service impact through kernel resource/reference leakage, not confidentiality or integrity compromise. No public exploit status is provided, so exploitation should not be assumed active.

Researcher notes

Evidence points to a refcount leak in the J1939 transport path after a second RTS handling case. The affected-version data in the bundle is broad and not distribution-specific. Validate against exact kernel source, config, loaded modules, and vendor backports before declaring exposure.

Mitigation direction

  • Apply Linux kernel or distribution updates that include the referenced stable fixes.
  • Check vendor advisories for backported fixes matching your deployed kernel build.
  • Prioritize systems using CAN/J1939 interfaces or virtual CAN testing environments.
  • If CAN/J1939 is unnecessary, review vendor-supported options to disable that exposure.
  • Track remediation through asset inventory rather than generic server patch queues.

Validation and detection

  • Inventory kernels and map them to vendor advisories for CVE-2026-22997.
  • Identify systems with CAN, vcan, or J1939 usage enabled.
  • Confirm patched kernels include an applicable referenced stable commit or vendor backport.
  • Review logs for unregister_netdevice waits involving CAN interfaces.
  • Test remediation in representative embedded or CAN-enabled environments before broad rollout.
Prepared
Confidence
medium
Sources
9

Public sources used

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

Potential ATT&CK relevance

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.

cve · low confidence lookup

CVE-2026-22997 mapping review

Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.

Open ATT&CK lookup
Vulnerability profileCVE Program record
Severity
High
CVSS
7.5 (3.1)
Known Exploited
No
Published

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Official CVE source material

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.

1CVSS vectors
3Timeline events
0ADP providers
8Source links

CVSS vector scores

1 official score

We 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.

ScoreVersionSeverityVectorExploitImpactSource
7.5CVSS 3.1HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H3.93.6Linux

Vulnerability scoring details

Base CVSS 3.1 score

7.5High
CVSS 3.1 vector shape for CVE-2026-22997Attack VectorAttack ComplexityPrivileges RequiredUser InteractionScopeConfidentiality ImpactIntegrity ImpactAvailability Impact

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Attack Vector
NetworkAdjacentLocalPhysical
Attack Complexity
LowHigh
Privileges Required
NoneLowHigh
User Interaction
NoneRequired
Scope
ChangedUnchanged
Confidentiality Impact
HighLowNone
Integrity Impact
HighLowNone
Availability Impact
HighLowNone

Vulnerability timeline

Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.

  1. CVE reservedCVE Program

    The CVE ID was reserved by the assigning CNA.

  2. CVE publishedCVE Program

    The CVE record was published.

  3. CVE updatedCVE Program

    The CVE record metadata indicates this as the latest update time.

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
LinuxLinux9d71dd0c70099914fcd063135da3c580865e924c, 9d71dd0c70099914fcd063135da3c580865e924c, 9d71dd0c70099914fcd063135da3c580865e924c, 9d71dd0c70099914fcd063135da3c580865e924c, 9d71dd0c70099914fcd063135da3c580865e924c, 9d71dd0c70099914fcd063135da3c580865e924c, 9d71dd0c70099914fcd063135da3c580865e924cunaffected
LinuxLinux5.4, 0, 5.10.249, 5.15.199, 6.1.162, 6.6.122, 6.12.67, 6.18.7, 6.19affected
Weakness

CWE details

No CWE listed

CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.