CVE-2019-11479
Description
Jonathan Looney discovered that the Linux kernel default MSS is hard-coded to 48 bytes. This allows a remote peer to fragment TCP resend queues significantly more than if a larger MSS were enforced. A remote attacker could use this to cause a denial of service. This has been fixed in stable kernel releases 4.4.182, 4.9.182, 4.14.127, 4.19.52, 5.1.11, and is fixed in commits 967c05aee439e6e5d7d805e195b3a20ef5c433d6 and 5f3e2bf008c2221478101ee72f5cb4654b9fc363.
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
Vendor advisory: debian — https://security-tracker.debian.org/tracker/CVE-2019-11479
Vendor advisory: suse — https://www.suse.com/security/cve/CVE-2019-11479.html
Vendor advisory: arch — https://security.archlinux.org/ASA-201906-13
Vendor advisory: arch — https://security.archlinux.org/ASA-201906-14
Vendor advisory: arch — https://security.archlinux.org/ASA-201906-15
Vendor advisory: arch — https://security.archlinux.org/ASA-201906-12
OS impact
| OS | Version | Status | Fixed in |
|---|---|---|---|
| arch | fixed | 5.1.11.a-1 | |
| sles | affected | | |
| debian | bookworm | fixed | 4.19.37-4 |
| debian | bullseye | fixed | 4.19.37-4 |
| debian | forky | fixed | 4.19.37-4 |
| debian | sid | fixed | 4.19.37-4 |
| debian | trixie | fixed | 4.19.37-4 |
References
Verify integrity in audit chain (admin only). AS-IS.