What’s Vulnerable › Vulnerabilities

CVE-2026-98793: netfilter: bpf: reject invalid NAT manipulation types

• Severity: unknown
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.2% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-10-18 · updated 2026-10-30

Description

In the Linux kernel, the following vulnerability has been resolved: netfilter: bpf: reject invalid NAT manipulation types As bpf_ct_set_nat_info() is not validating the NAT manipulation type a wrong value can be passed directly to nf_nat_setup_info(). This triggers the WARN_ON() at nf_nat_setup_info() and if panic_on_warn isn't set, then IPS_SRC_NAT_DONE is set without adding nat_bysource and conntrack cleanup tries to unlink an uninitialized hlist node. Fix this by checking that NAT manipulation type is correct before calling nf_nat_setup_info(). In addition, if the WARN_ON is hit, return NF_DROP instead of continuing with the processing to avoid similar situations in the future.

Affected products

• Linux: 6.1 — fixed in 7.3

How to fix

Upgrade to a fixed version: Linux 7.3. Check the vendor advisory for mitigations.

References

• https://git.kernel.org/stable/c/16d464013ec2267b00a83f4bfbb97b3ecc63bfa7
• https://git.kernel.org/stable/c/58108f05b0502448f6bb612ee2eccc63bd6449cb
• https://git.kernel.org/stable/c/752492947be3123ea6c689e2f93ae04ecd675d42
• https://git.kernel.org/stable/c/ce7b41f0e4b5db0580d0a2059a0c9e672b461b5e
• https://git.kernel.org/stable/c/ea777dc90ab37e64fa4b92f6fcf3b5edcef5e058
• https://git.kernel.org/stable/c/f6143ae109df56d51d5536e813deb19eee7a6205

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