CVE-2026-99999

critical

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.

References

https://github.com/vulnerability-lookup/vulniverse

https://github.com/agiwhitelist/factgate

https://github.com/razo7/vigil

https://github.com/lasdjk/CVE-2026-99999-important-info

https://vercel.com/blog/findings-from-the-1-million-dollar-vercel-sandbox-challenge

https://pwn.ai/blog/Pwnescape

https://git.kernel.org/stable/c/f3e835af6226f1dd12160cbd696081e9b6155de0

https://git.kernel.org/stable/c/c3e33464746166264334641dc850a36eef7e6326

https://git.kernel.org/stable/c/a65f69e0f38ffbed1b128029e09097436416dc8b

https://git.kernel.org/stable/c/a464d950f31c89565cbaae038cc60db04fe01956

https://git.kernel.org/stable/c/94524b7b32691de2e2ce162c04d6cbc9106e5cbf

https://git.kernel.org/stable/c/6785011f8b16abf40b1e9d8b2e332232b3e68822

https://git.kernel.org/stable/c/32a8b0adaa18e52aaa0b246b5ffe683075354dbb

https://git.kernel.org/stable/c/0fab003ef4698e0628060a45a48f14b43ba2a40a

https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-102044

http://www.openwall.com/lists/oss-security/2026/10/15/5

Details

Source: Mitre, NVD

Published: 2026-10-15

Updated: 2026-10-15

Named Vulnerability: PwnEscape

Risk Information

CVSS v2

Base Score: 7.2

Vector: CVSS2#AV:L/AC:L/Au:N/C:C/I:C/A:C

Severity: High

CVSS v3

Base Score: 9.3

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

Severity: Critical