CVE-2026-43037 remediation guide

Linux Linux, NVIDIA for RHEL 10, Red Hat Enterprise Linux 10

In the Linux kernel, the following vulnerability has been resolved: ip6_tunnel: clear skb2->cb[] in ip4ip6_err() Oskar Kjos reported the following problem. ip4ip6_err() calls icmp_send() on a cloned skb whose cb[] was written by the IPv6 receive path as struct inet6_skb_parm. icmp_send() passes IPCB(skb2) to __ip_options_echo(), which interprets that cb[] region as struct inet_skb_parm (IPv4). The layouts differ: inet6_skb_parm.nhoff at offset 14 overlaps inet_skb_parm.opt.rr, producing a non-zero rr value. __ip_options_echo() then reads optlen from attacker-controlled packet data at sptr[r...

Open CVE record

ProductLinux Linux, NVIDIA for RHEL 10, Red Hat Enterprise Linux 10

Affected versions>= c4d3efafcc933fd2ffd169d7dc4f980393a13796 < ea9f65b27c8404e164848ebff1443310fd187629, >= c4d3efafcc933fd2ffd169d7dc4f980393a13796 < d6621f60192fe10c047a4487be42a6f4c150707f, >= c4d3efafcc933fd2ffd169d7dc4f980393a13796 < 2cc6e3b0fe0f0242d1f530a93a4924f48ab85ba5, >= c4d3efafcc933fd2ffd169d7dc4f980393a13796 < a0c4ce9900a108eaf55d0f3b399cb55999647d39, >= c4d3efafcc933fd2ffd169d7dc4f980393a13796 < 1063515ce15ff31065c4e7f8265f4c2fd3c54876, >= c4d3efafcc933fd2ffd169d7dc4f980393a13796 < 590f622669b97eaf7b57a1de7b0a6e68c5d8b2c3, >= c4d3efafcc933fd2ffd169d7dc4f980393a13796 < 4a622658f384b03560834cbe8ffcfe69a278f7c8, >= c4d3efafcc933fd2ffd169d7dc4f980393a13796 < 2edfa31769a4add828a7e604b21cb82aaaa05925, >= 2.6.22, >= 2.6.22 < 5.10.253, >= 5.11 < 5.15.203, >= 5.16 < 6.1.168, >= 6.2 < 6.6.134, >= 6.7 < 6.12.81, >= 6.13 < 6.18.22, >= 6.19 < 6.19.12, 7.0

Fixed versions5.10.253, 5.15.203, 6.1.168, 6.6.134, 6.12.81, 6.18.22, 6.19.12

Priority basisReview · CVSS 9.8 · EPSS 0.56%

Identify the affected asset

Confirm whether Linux Linux, NVIDIA for RHEL 10, Red Hat Enterprise Linux 10 is installed, record the deployed version and installation path, and identify exposed interfaces.

Record the product name, package or appliance identifier, and installed version.
Identify internet-facing, administrative, API, and internal access paths.
Preserve the pre-change configuration and relevant service logs.

Validate the affected-version match

Compare the deployed version with the affected range: >= c4d3efafcc933fd2ffd169d7dc4f980393a13796 < ea9f65b27c8404e164848ebff1443310fd187629, >= c4d3efafcc933fd2ffd169d7dc4f980393a13796 < d6621f60192fe10c047a4487be42a6f4c150707f, >= c4d3efafcc933fd2ffd169d7dc4f980393a13796 < 2cc6e3b0fe0f0242d1f530a93a4924f48ab85ba5, >= c4d3efafcc933fd2ffd169d7dc4f980393a13796 < a0c4ce9900a108eaf55d0f3b399cb55999647d39, >= c4d3efafcc933fd2ffd169d7dc4f980393a13796 < 1063515ce15ff31065c4e7f8265f4c2fd3c54876, >= c4d3efafcc933fd2ffd169d7dc4f980393a13796 < 590f622669b97eaf7b57a1de7b0a6e68c5d8b2c3, >= c4d3efafcc933fd2ffd169d7dc4f980393a13796 < 4a622658f384b03560834cbe8ffcfe69a278f7c8, >= c4d3efafcc933fd2ffd169d7dc4f980393a13796 < 2edfa31769a4add828a7e604b21cb82aaaa05925, >= 2.6.22, >= 2.6.22 < 5.10.253, >= 5.11 < 5.15.203, >= 5.16 < 6.1.168, >= 6.2 < 6.6.134, >= 6.7 < 6.12.81, >= 6.13 < 6.18.22, >= 6.19 < 6.19.12, 7.0. Treat incomplete inventory results as unresolved.

Prioritize with independent signals

The CVSS severity warrants an early asset and exposure review. Combine this signal with asset criticality, exposure, compensating controls, and business impact.

Apply supported remediation

Follow the vendor advisory or supported update path. Current fixed-version status: 5.10.253, 5.15.203, 6.1.168, 6.6.134, 6.12.81, 6.18.22, 6.19.12. Preserve configuration and rollback material before change.

Verify the result

Confirm the resulting version, service health, authentication and access paths, monitoring coverage, and relevant security logs.

Confirm the expected version and package state.
Run a functional health check for critical service paths.
Review authentication, error, application, and security monitoring logs.
Reassess exposure if the supported fix cannot be applied.

Operational boundary

This page does not replace the vendor advisory, support contract, change-management process, or recovery plan. Do not infer that an asset is unaffected from an incomplete inventory query or a missing fixed-version field.