CVE-2026-43057
What it is
In the Linux kernel, the following vulnerability has been resolved: net: correctly handle tunneled traffic on IPV6_CSUM GSO fallback NETIF_F_IPV6_CSUM only advertises support for checksum offload of packets without IPv6 extension headers. Packets with extension headers must fall back onto software checksumming. Since TSO depends on checksum offload, those must revert to GSO. The below commit introduces that fallback. It always checks network header length. For tunneled packets, the inner header length must be checked instead. Extend the check accordingly. A special case is tunneled packets without inner IP protocol. Such as RFC 6951 SCTP in UDP. Those are not standard IPv6 followed by transport header either, so also must revert to the software GSO path.
At a glance
- Exploitability
- Can be exploited over the network without logging in. High risk of service disruption.
- Exploit odds
- 0.4% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.4% in the next 30 days (EPSS).
- Severity: 7.5 HIGH (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.4% · EPSS, next 30 days
- Record status
- Modified
Affected
- Linux Kernel < 6.1.168
- Linux Kernel < 6.6.134
- Linux Kernel < 6.12.81
- Linux Kernel < 6.17
- Linux Kernel < 6.18.22
- Linux Kernel < 6.19.12
- Linux Kernel 6.17
- Linux Kernel 7.0
Attack profile CVSS 3.1 · 7.5
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Raw vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2026-43057.md and follow it. Check whether this project is affected by CVE-2026-43057. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- https://git.kernel.org/stable/c/2094a7cf91b71367b649f991aacc7b579f793d0b
- https://git.kernel.org/stable/c/33670f780e0120c3dacda188c512bbffe0b6044c
- https://git.kernel.org/stable/c/732fdeb2987c94b439d51f5cb9addddc2fc48c42
- https://git.kernel.org/stable/c/a98b78116a27e2a57b696b569b2cb431c95cf9b6
- https://git.kernel.org/stable/c/c4336a07eb6b2526dc2b62928b5104b41a7f81f5
- https://git.kernel.org/stable/c/ed71cf465c75f5688b07a35d373cd1d6b589c8ea
References
- https://git.kernel.org/stable/c/2094a7cf91b71367b649f991aacc7b579f793d0b
- https://git.kernel.org/stable/c/33670f780e0120c3dacda188c512bbffe0b6044c
- https://git.kernel.org/stable/c/732fdeb2987c94b439d51f5cb9addddc2fc48c42
- https://git.kernel.org/stable/c/a98b78116a27e2a57b696b569b2cb431c95cf9b6
- https://git.kernel.org/stable/c/c4336a07eb6b2526dc2b62928b5104b41a7f81f5
- https://git.kernel.org/stable/c/ed71cf465c75f5688b07a35d373cd1d6b589c8ea
- https://cert-portal.siemens.com/productcert/html/ssa-019113.html
- https://cert-portal.siemens.com/productcert/html/ssa-082556.html
- https://cert-portal.siemens.com/productcert/html/ssa-457936.html