In the Linux kernel, the following vulnerability has been resolved: net: skbuff: don't leave stale bytes in skb_copy_and_csum_bits() Wh…
CVE-2026-99030 · GHSA-2m74-g73v-pv5c · EUVD-2026-108825 · published 23 Oct 2026
How serious is it
- Severity: high, CVSS score 7.5 out of 10.
- No exploit prediction (EPSS) score yet.
- Not on the CISA list of exploited vulnerabilities.
- No public exploit in Exploit-DB.
Is your app affected by CVE-2026-99030?
Paste this prompt into Claude Code, Cursor or any AI coding tool: it runs a free Shippable scan of your project and fixes what it finds. Built with Lovable, Bolt or v0? Scan your live app. Or upload your package file.
Who is affected
- Linux Linux: 65249feb6b3df9e17bab5911ee56fa7b0971e231 <ab9414ed70bd783e902a85c350620dee269bcb2b
- Linux Linux: 6.12
- Linux Linux: patch: 6.18.57
- Linux Linux: patch: 7.3
- Linux Linux: 65249feb6b3df9e17bab5911ee56fa7b0971e231 <5551399751e2c9f31e4f3428040985a07e79d9c2
- Linux Linux: 65249feb6b3df9e17bab5911ee56fa7b0971e231 <39d1a6b601831237c6038b5e3ac8dbb883c1700a
- Linux Linux: patch: 7.2.11
- Linux Linux: patch: 0
- Linux Linux: 65249feb6b3df9e17bab5911ee56fa7b0971e231 <5f19b9cfff79508e8cb09be40d014cb0807f3854
- Linux Linux: patch: 6.12.113
How to check
- Find out whether you run the affected product and which version, then compare it with the versions above.
How to fix
Copies a prompt for Claude Code, Cursor or Codex that asks it to check whether you run this product.
- Apply the vendor's update or mitigation from the references below. If there is none yet, limit exposure of the affected service until there is.
- If a vulnerable version was live, check your logs and rotate the secrets that server could read.
The advisory
In the Linux kernel, the following vulnerability has been resolved:
net: skbuff: don't leave stale bytes in skb_copy_and_csum_bits()
When skb_copy_and_csum_bits() reaches unreadable frags it returns 0
after copying only the linear part, and the rest of the caller's buffer
is left as it was. The callers copy into a buffer that is about to go
out on the wire: an ICMP error quoting the offending packet, or a
driver's TX bounce buffer in skb_copy_and_csum_dev(). Neither buffer
is zeroed beforehand, so whatever was in memory there gets sent.
Zero the part of the buffer we didn't fill. The checksum usually
won't match the data any more, so the receiver will usually drop the
packet, but either way it no longer carries anything it shouldn't.
Only zero for a positive @len, a negative one from a broken caller must
not turn into a huge memset().
Check your whole app
Dependencies are only half of it. Free and read-only: before you push, run npx shippable-dev scan localhost:3000 in your project folder, no account needed. For your live app, you prove it's yours with a one-line tag first.
References
- git.kernel.org/stable/c/5f19b9cfff79508e8cb09be40d014cb0807f3854
- git.kernel.org/stable/c/5551399751e2c9f31e4f3428040985a07e79d9c2
- git.kernel.org/stable/c/39d1a6b601831237c6038b5e3ac8dbb883c1700a
- git.kernel.org/stable/c/ab9414ed70bd783e902a85c350620dee269bcb2b
- nvd.nist.gov/vuln/detail/CVE-2026-99030
Merged from ENISA EUVD. Last updated 25 Oct 2026. All vulnerabilities · RSS · JSON