CVE-2026-99999ipv4: validate checksum_start before completing checksum
Updated under an hour ago ()
Does this affect you?
It affects Linux. Add what you run to find out whether that includes you.
EPSS puts the chance of exploitation in the next 30 days at 0.21%, higher than 11% of scored CVEs.
Do this next
Free account, 1 product
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.
- CVSS
- 9.3 CRITICAL (v3.1, CNA)CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
- Weakness (CWE)
- Not given
- Known exploited
- Not in CISA's KEV catalog
- EPSS (exploitation in the next 30 days)
- 0.21% (percentile 11)
- Assigned by
- Linux
- NVD analysis
- Received
- Record last updated
- Oct 17, 2026
- First seen by InfoSec Signals
- Oct 15, 2026
Affected products
Linux Linux linux:linux (from the name) | from f43798c27684ab925adde7d8acc34c78c6e50df8 before a464d950f31c89565cbaae038cc60db04fe01956; from f43798c27684ab925adde7d8acc34c78c6e50df8 before 0fab003ef4698e0628060a45a48f14b43ba2a40a; from f43798c27684ab925adde7d8acc34c78c6e50df8 before 94524b7b32691de2e2ce162c04d6cbc9106e5cbf; from f43798c27684ab925adde7d8acc34c78c6e50df8 before a65f69e0f38ffbed1b128029e09097436416dc8b; from f43798c27684ab925adde7d8acc34c78c6e50df8 before 32a8b0adaa18e52aaa0b246b5ffe683075354dbb; from f43798c27684ab925adde7d8acc34c78c6e50df8 before f3e835af6226f1dd12160cbd696081e9b6155de0; from f43798c27684ab925adde7d8acc34c78c6e50df8 before c3e33464746166264334641dc850a36eef7e6326; from f43798c27684ab925adde7d8acc34c78c6e50df8 before 6785011f8b16abf40b1e9d8b2e332232b3e68822 | CNA record |
References
- https://git.kernel.org/stable/c/a464d950f31c89565cbaae038cc60db04fe01956
- https://git.kernel.org/stable/c/0fab003ef4698e0628060a45a48f14b43ba2a40a
- https://git.kernel.org/stable/c/94524b7b32691de2e2ce162c04d6cbc9106e5cbf
- https://git.kernel.org/stable/c/a65f69e0f38ffbed1b128029e09097436416dc8b
- https://git.kernel.org/stable/c/32a8b0adaa18e52aaa0b246b5ffe683075354dbb
- https://git.kernel.org/stable/c/f3e835af6226f1dd12160cbd696081e9b6155de0
- https://git.kernel.org/stable/c/c3e33464746166264334641dc850a36eef7e6326
- https://git.kernel.org/stable/c/6785011f8b16abf40b1e9d8b2e332232b3e68822
- https://pwn.ai/blog/pwnescape
- https://vercel.com/blog/findings-from-the-1-million-dollar-vercel-sandbox-challenge
- https://pwn.ai/blog/Pwnescape
- http://www.openwall.com/lists/oss-security/2026/10/15/5
The CVE record on cve.org NVD's entry
The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.