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CVE Record

CVE-2023-1281: UAF in Linux kernel's tcindex (traffic control index filter) implementation

Use After Free vulnerability in Linux kernel traffic control index filter (tcindex) allows Privilege Escalation. The imperfect hash area can be updated while packets are traversing, which will cause a use-after-free when 'tcf_exts_exec()' is called with the destroyed tcf_ext. A local attacker user can use this vulnerability to elevate its privileges to root. This issue affects Linux Kernel: from 4.14 before git commit ee059170b1f7e94e55fa6cadee544e176a6e59c2.

HighCVSS 7.8Not KEV-listedUpdated
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Glexia's TakeAutomated analysishigh

Security readout for executives and security teams

Plain-English summary

A flaw in the Linux kernel’s tcindex traffic-control filter can let a local, low-privileged attacker gain root privileges. Successful exploitation could expose data, alter systems, or cause outages. This is not described as a remote attack.

Executive priority

Prioritize remediation on multi-user systems, shared compute, administrative jump hosts, and other machines where untrusted users can obtain local access. Treat internet exposure alone as an insufficient indicator because the vulnerability is local. Accelerate patching where compromise would expose sensitive data or critical operations.

Technical view

CVE-2023-1281 is a use-after-free in tcindex. The imperfect-hash area can be changed while packets are traversing it, leaving tcf_exts_exec() to access a destroyed tcf_ext. The supplied record identifies Linux kernels from 4.14 until the correction in commit ee059170b1f7e94e55fa6cadee544e176a6e59c2.

Likely exposure

Potential exposure includes systems running affected Linux kernel code before the cited correction, particularly where untrusted users have local access. Distribution kernels may contain backported fixes despite older version numbers, so version strings alone are insufficient. The supplied evidence does not fully define every prerequisite needed to reach the vulnerable tcindex path.

Exploitation context

The CVSS 3.1 score is 7.8: local access and low privileges are required, with no user interaction. Successful exploitation may provide root privileges and high confidentiality, integrity, and availability impact. The source bundle marks this CVE as absent from KEV and provides no evidence of active exploitation.

Researcher notes

The central exposure question is whether the running distribution kernel includes the upstream correction or an equivalent backport. The provided record does not establish exploit availability, active exploitation, all triggering permissions, or whether every listed vendor kernel is vulnerable. Validate against distributor-specific advisories rather than relying solely on upstream version comparisons.

Mitigation direction

  • Install a vendor-supported kernel update containing commit ee059170b1f7e94e55fa6cadee544e176a6e59c2 or its equivalent backport.
  • Reboot affected systems into the corrected kernel after applying the update.
  • Consult the operating-system vendor’s advisory because distribution version numbers and backport status differ.
  • Until remediation, reduce untrusted local access and closely monitor unexpected privilege changes.

Validation and detection

  • Inventory running kernel versions across physical hosts, virtual machines, containers’ hosts, appliances, and cloud images.
  • Compare each kernel package against its distributor’s CVE advisory and backport information.
  • Verify the installed kernel contains the cited correction or an explicitly documented equivalent fix.
  • After rebooting, confirm the running kernel is the corrected build rather than an older installed image.
Prepared
Confidence
high
Sources
5

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

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cwe · low confidence lookup

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description · low confidence lookup

Privilege behavior lookup

The CVE wording references privilege impact, so privilege escalation and authorization behavior review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.

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cve · low confidence lookup

CVE-2023-1281 mapping review

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Vulnerability profileCVE Program record
Severity
High
CVSS
7.8 (3.1)
Known Exploited
No
Published

Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/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
2ADP providers
6Source links

SSVC decision data

CISA-ADPCISA Coordinator
Timestamp
Version
2.0.3
Exploitation: noneAutomatable: noTechnical Impact: total

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
7.8CVSS 3.1HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H1.85.9Google

Vulnerability scoring details

Base CVSS 3.1 score

7.8High
CVSS 3.1 vector shape for CVE-2023-1281Attack VectorAttack ComplexityPrivileges RequiredUser InteractionScopeConfidentiality ImpactIntegrity ImpactAvailability Impact

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

ADP provider summaries

CVECVE Program Container
CISA-ADPCISA ADP Vulnrichment
other:ssvc

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
LinuxLinux Kernelkernel, 4.14.0, 5.11.0, 5.16.0, 6.2.0, ee059170b1f7e94e55fa6cadee544e176a6e59c2unaffected
Weakness

CWE details

CWE-416

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

CWE-416 · source CWE mapping

Use After Free

Use After Free represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.

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