Vulnerability report

Exploited in the wild Confirmed confidence In CISA KEV

CVE-2024-36971

net: fix __dst_negative_advice() race

Linux · 4.6

Watch CVE-2024-36971 Browse KEV feed
Severity
CVSS 7.8 · High
Confidence
Confirmed
Exploit status
Exploited in the wild
EPSS
2.7%
First observed
—
Last observed
—

Decision summary

What security teams need to know first

Direct answers before the deeper technical record.

What it is

CVE-2024-36971 is net: fix __dst_negative_advice() race affecting Linux. In the Linux kernel, the following vulnerability has been resolved: net: fix __dst_negative_advice() race __dst_negative_advice() does not...

Is it exploited?

Yes. Previdian tracks this CVE as a known exploited vulnerability. Confidence is confirmed. Listed in CISA KEV. Also confirmed by third-party sources.

Who is affected?

Linux 4.6.

What should we do?

Prioritize remediation. Validate affected assets and apply vendor fixes on an accelerated timeline.

Overview

net: fix __dst_negative_advice() race

In the Linux kernel, the following vulnerability has been resolved:

net: fix __dst_negative_advice() race

__dst_negative_advice() does not enforce proper RCU rules when sk->dst_cache must be cleared, leading to possible UAF.

RCU rules are that we must first clear sk->sk_dst_cache, then call dst_release(old_dst).

Note that sk_dst_reset(sk) is implementing this protocol correctly, while __dst_negative_advice() uses the wrong order.

Given that ip6_negative_advice() has special logic against RTF_CACHE, this means each of the three ->negative_advice() existing methods must perform the sk_dst_reset() themselves.

Note the check against NULL dst is centralized in __dst_negative_advice(), there is no need to duplicate it in various callbacks.

Many thanks to Clement Lecigne for tracking this issue.

This old bug became visible after the blamed commit, using UDP sockets.

linux Affected
linux_kernel
4.6 Before 051c0bde9f04 Before db0082825037 Before 2295a7ef5c8c Before eacb8b195579 Before 81dd3c82a456 Before 5af198c38712 Before b8af8e6118a6 Before 92f1655aa2b2
linux Unaffected
linux_kernel
Before 4.6 Before 4.20 Before 5.5 Before 5.11 Before 5.16 Before 6.2 Before 6.7 Before 6.10 Through *
Linux Affected
Linux
Before 051c0bde9f0450a2ec3d62a86d2a0d2fad117f13 Before db0082825037794c5dba9959c9de13ca34cc5e72 Before 2295a7ef5c8c49241bff769e7826ef2582e532a6 Before eacb8b195579c174a6d3e12a9690b206eb7f28cf Before 81dd3c82a456b0015461754be7cb2693991421b4 Before 5af198c387128a9d2ddd620b0f0803564a4d4508 Before b8af8e6118a6605f0e495a58d591ca94a85a50fc Before 92f1655aa2b2294d0b49925f3b875a634bd3b59e 4.6
Linux Unaffected
Linux
Before 4.6 Through 4.19.* Through 5.4.* Through 5.10.* Through 5.15.* Through 6.1.* Through 6.6.* Through 6.9.* Through *
Published
10 Jun 2024
Exploitation Reported
07 Aug 2024
Attack vector
Local
Complexity
Low
Privileges
Low
User interaction
None

Tags

linux nessus_scanner windows cisa

CVE References

Exploitation evidence

Why Previdian marks this CVE as exploited

Third-party attestation and first-party sensor observation are shown separately so teams can judge the evidence chain.

Exploited in the wild

CISA

Recorded 07 Aug 2024

A trusted third party reported exploitation.

Known exploited vulnerability sources

Per-source evidence links for KEV attestations are available through the Previdian Pro API.

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Source Added
CISA First 2024-08-07 00:00 UTC
CVE 2026-06-05 09:46 UTC

Detection

Operational artifacts and observed signals

Make the evidence actionable in scanner, SOC, and edge-control workflows.

Observed signals

Request targets
User-Agents
Callback hosts
0
0
0

Request targets and User-Agents available in Pro. Callback host details available in Enterprise.

Virtual patch status

No Previdian virtual patch is currently available. Future rules ship for ModSecurity, Cloudflare, and AWS WAF.

Learn about virtual patches →

Scanner Artifacts

Scanner and exploit-framework references linked to this CVE.

Scanner Reference Detected
Nessus https://www.tenable.com/plugins/nessus/215599 02 Jun 2025

Risk and context

Severity, weaknesses, and research context

CVSS v3.1

7.8 High

Potential damage if exploited. Separate from whether attackers are using it.

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

EPSS

2.7%

Estimated chance of exploitation in the next 30 days. Previdian's warning comes from evidence, not this score.

Weaknesses

Use After Free CWE-416

Timeline

From disclosure to observed exploitation

  1. 09:46 UTC

    KEV confirmed by CVE

    Exploitation attested by an external source

  2. 09:26 UTC

    Nessus plugin available

    Scanner coverage available

  3. 00:00 UTC

    Added to CISA KEV

    Listed in the CISA Known Exploited Vulnerabilities catalog

  4. 09:03 UTC

    CVE published

    Vulnerability disclosed publicly

  5. 15:25 UTC

    CVE ID reserved

    Identifier reserved by the CNA

Pro API

Automate this intelligence

Confidence, exploit status, sensor telemetry, PoCs, scanner integrations, mentions, and tags are available programmatically for VM, SOC, and CTI workflows.

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  • Evidence confidence and provenance
  • First-party sensor telemetry
  • PoC and scanner references
  • Affected versions and enrichment
  • Automation-ready JSON delivery

GET /api/v2/pro/kevs/CVE-2024-36971

Free JSON includes basic KEV fields 
{
  "cve_id": "CVE-2024-36971",
  "confidence": "Confirmed",
  "cvss_score": 7.8,
  "cvss_estimated": false,
  "epss_score": 0.02701,
  "exploit_status": {
    "exploited_in_the_wild": true,
    "active_exploitation_observed": false
  },
  "sensor_telemetry": { "attempts": 0, "sensors": 0 }
}