LiveActive security incident?Get immediate response
CVE Record

CVE-2026-22987: net/sched: act_api: avoid dereferencing ERR_PTR in tcf_idrinfo_destroy

In the Linux kernel, the following vulnerability has been resolved: net/sched: act_api: avoid dereferencing ERR_PTR in tcf_idrinfo_destroy syzbot reported a crash in tc_act_in_hw() during netns teardown where tcf_idrinfo_destroy() passed an ERR_PTR(-EBUSY) value as a tc_action pointer, leading to an invalid dereference. Guard against ERR_PTR entries when iterating the action IDR so teardown does not call tc_act_in_hw() on an error pointer.

UnknownCVSS not scoredNot KEV-listedUpdated
Discuss exposureBack to CVEs
Glexia's TakeAutomated analysisunknown

Security readout for executives and security teams

Plain-English summary

CVE-2026-22987 is a Linux kernel crash bug in traffic-control action cleanup during network namespace teardown. The kernel could treat an internal error value as a real action object and dereference it, causing an invalid memory access. The public bundle does not provide CVSS, confirmed impact beyond crash, or evidence of active exploitation.

Executive priority

Treat as a stability and availability risk until vendor severity is published. Prioritize routine kernel maintenance, with faster action for shared hosts, container platforms, and systems relying heavily on Linux traffic control.

Technical view

The flaw is in net/sched act_api. During tcf_idrinfo_destroy(), an ERR_PTR(-EBUSY) entry could be passed as a tc_action pointer to tc_act_in_hw(), causing invalid dereference. The fix guards against ERR_PTR entries while iterating the action IDR during teardown.

Likely exposure

Exposure appears limited to Linux systems running affected kernel versions or builds containing the vulnerable net/sched act_api code. The bundle lists Linux kernel version markers including 6.17, 6.18.6, and 6.19, but does not map distro package versions or configurations.

Exploitation context

The issue was reported by syzbot as a crash during network namespace teardown. The provided sources do not state active exploitation, public exploit availability, required privileges, or remote reachability. KEV status is false in the bundle.

Researcher notes

Evidence supports an invalid dereference in cleanup logic, not a demonstrated privilege escalation or remote compromise. The affected-version data is incomplete for distro mapping, so validation should focus on commit presence and vendor backports.

Mitigation direction

  • Review Linux vendor advisories for the kernel package used in your environment.
  • Upgrade to a kernel containing the referenced stable fixes when available.
  • Prioritize hosts using traffic control features, network namespaces, or dense container workloads.
  • Track distro backports because fixed package versions may differ from upstream kernel numbers.

Validation and detection

  • Inventory running kernel versions across servers, appliances, and container hosts.
  • Check whether deployed kernels include the referenced stable commits or vendor backports.
  • Review crash logs for net/sched, tcf_idrinfo_destroy, tc_act_in_hw, or netns teardown signatures.
  • Confirm remediation through package metadata, kernel changelogs, or vendor advisory references.
Prepared
Confidence
medium
Sources
4

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-2026-22987 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
Unknown
CVSS
Not scored
Known Exploited
No
Published
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.

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

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
LinuxLinux84a7d6797e6a03705e6b48c613fa424662049d87, 84a7d6797e6a03705e6b48c613fa424662049d87unaffected
LinuxLinux6.17, 0, 6.18.6, 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.