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

ipv4: validate checksum_start before completing checksum

If a packet with bad checksum metadata gets into the ipv4 stack,
skb_checksum_help can corrupt the network header and cause a bunch of
mischief.

This was discovered and reported by Paulos, and has been reporoduced
by others independently since.

We really shouldn't allow such packets in, but as a defence
in depth measure, let's also check before we complete the checksum.

A more complete validation at input is forthcoming, but needs more work.

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Advisories
Source ID Title
Debian DSA Debian DSA DSA-6568-1 linux security update
Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Fri, 16 Oct 2026 17:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}


Fri, 16 Oct 2026 12:30:00 +0000


Fri, 16 Oct 2026 07:30:00 +0000

Type Values Removed Values Added
Weaknesses CWE-119
CWE-20

Thu, 15 Oct 2026 23:30:00 +0000

Type Values Removed Values Added
References

Thu, 15 Oct 2026 13:30:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: ipv4: validate checksum_start before completing checksum If a packet with bad checksum metadata gets into the ipv4 stack, skb_checksum_help can corrupt the network header and cause a bunch of mischief. This was discovered and reported by Paulos, and has been reporoduced by others independently since. We really shouldn't allow such packets in, but as a defence in depth measure, let's also check before we complete the checksum. A more complete validation at input is forthcoming, but needs more work.
Title ipv4: validate checksum_start before completing checksum
First Time appeared Linux
Linux linux Kernel
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel
References
Metrics cvssV3_1

{'score': 9.3, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H'}


Projects

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cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2026-10-16T15:49:17.183Z

Reserved: 2026-09-25T10:25:14.451Z

Link: CVE-2026-99999

cve-icon Vulnrichment

Updated: 2026-10-15T22:07:24.590Z

cve-icon NVD

Status : Received

Published: 2026-10-15T13:17:14.137

Modified: 2026-10-16T16:23:05.347

Link: CVE-2026-99999

cve-icon Redhat

Severity : Critical

Publid Date: 2026-10-15T00:00:00Z

Links: CVE-2026-99999 - Bugzilla

cve-icon OpenCVE Enrichment

Updated: 2026-10-16T07:15:17Z

Weaknesses