CVE-2026-53002Network attack vector

Kernel stack corruption via SIP length formatting

Published Jun 24, 2026 · Updated Jun 24, 2026

Out-of-bounds write in the Linux Kernel netfilter SIP helper allows remote attackers to corrupt kernel stack memory via crafted SIP traffic. The mangle_content_len() path uses sprintf() to write a rewritten Content-Length value into a stack buffer that can be too small. Reachability requires conntrack SIP/NAT processing; the published KASAN trace demonstrates a one-byte stack overwrite, while public sources document no code execution.

CVSS severity9.8
Critical
EPSS probability0.37%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Out-of-bounds write in the Linux Kernel netfilter SIP helper allows remote attackers to corrupt kernel stack memory via crafted SIP traffic. The mangle_content_len() path uses sprintf() to write a rewritten Content-Length value into a stack buffer that can be too small. Reachability requires conntrack SIP/NAT processing; the published KASAN trace demonstrates a one-byte stack overwrite, while public sources document no code execution.

The record

CVE
CVE-2026-53002
Published
Jun 24, 2026
Updated
Jun 24, 2026
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
CWE-787, T1499
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 24, 2026CVE publishedPublication date reported by the CVE source.
  2. Jun 24, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=2.6.20
  2. Affected versionversion=9fafcd7b203229c3f3893a475741afc27e276306 <1c9fb8aeed06790d42cdcd00f6c3ce0b9e926c1e
  3. Affected versionversion=9fafcd7b203229c3f3893a475741afc27e276306 <2f793ba78470a99f40389b7dc60a81d9f5ad3956
  4. Affected versionversion=9fafcd7b203229c3f3893a475741afc27e276306 <6bbf829b4c1b44c941c47dd0d710f1393258f3d5
  5. Affected versionversion=9fafcd7b203229c3f3893a475741afc27e276306 <6e7066bdb481a87fe88c4fa563e348c03b2d373d
  6. Affected versionversion=9fafcd7b203229c3f3893a475741afc27e276306 <8e3be0d12615a173fe260cd42753ca7a001acbf2
  7. Affected versionversion=9fafcd7b203229c3f3893a475741afc27e276306 <a8e0a32a23d3f34862af3b4da792ecb3a891a9a3
  8. Affected versionversion=9fafcd7b203229c3f3893a475741afc27e276306 <ab64e61c9323fa6de21bd20da1ddb29a0fb65d34
  9. Affected versionversion=9fafcd7b203229c3f3893a475741afc27e276306 <c08ff52e44945e6ef4ce0790f49ea761b060c45b

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

The Linux Kernel Organization · Linux Kernelversion=2.6.20; version=9fafcd7b203229c3f3893a475741afc27e276306 <1c9fb8aeed06790d42cdcd00f6c3ce0b9e926c1e; version=9fafcd7b203229c3f3893a475741afc27e276306 <2f793ba78470a99f40389b7dc60a81d9f5ad3956; version=9fafcd7b203229c3f3893a475741afc27e276306 <6bbf829b4c1b44c941c47dd0d710f1393258f3d5; version=9fafcd7b203229c3f3893a475741afc27e276306 <6e7066bdb481a87fe88c4fa563e348c03b2d373d; version=9fafcd7b203229c3f3893a475741afc27e276306 <8e3be0d12615a173fe260cd42753ca7a001acbf2; version=9fafcd7b203229c3f3893a475741afc27e276306 <a8e0a32a23d3f34862af3b4da792ecb3a891a9a3; version=9fafcd7b203229c3f3893a475741afc27e276306 <ab64e61c9323fa6de21bd20da1ddb29a0fb65d34; version=9fafcd7b203229c3f3893a475741afc27e276306 <c08ff52e44945e6ef4ce0790f49ea761b060c45b

Published CVSS scores

9.8kernel.orgCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
7.0Red HatCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-787Out-of-bounds Write
T1499Endpoint Denial of Service

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

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