netfilter: nft_nat: fully initialise new_addr in netmap setup

Summary

In the Linux kernel, the following vulnerability has been resolved: netfilter: nft_nat: fully initialise new_addr in netmap setup nft_nat_setup_netmap() builds the mapped address in an on-stack union nf_inet_addr. For an IPv4 mapping it writes only the 4-byte .ip member and the loop runs a single 32-bit iteration, but it then copies the whole 16-byte union into range->min_addr and range->max_addr, so the upper 12 bytes reach nf_nat_setup_info() uninitialised. KMSAN reports an uninit-value in nf_nat_setup_info() reached from nft_nat_eval(). The IPv6 path fills all 16 bytes and is not affected. Zero-initialise new_addr.

Timeline

1. Oct 6, 2026, 8:46 AM UTCCVE published
2. Oct 19, 2026, 9:17 AM UTCRecord last updated

Affected versions

• Linux Linux

  From 3ff7ddb1353da9b535e65702704cbadea1da9a00 · fixed in 29365695842db0a97b701a43a09fad1b4f7ecf3e; From 3ff7ddb1353da9b535e65702704cbadea1da9a00 · fixed in 7b9380c38c2fd2189416fa602bdbc5c8523b84b2; From 3ff7ddb1353da9b535e65702704cbadea1da9a00 · fixed in eb2030137dba3b59cbb5057a33af70488d6bc231; From 3ff7ddb1353da9b535e65702704cbadea1da9a00 · fixed in e4982c489ee359162eee3ece1fb36082648464a5; From 3ff7ddb1353da9b535e65702704cbadea1da9a00 · fixed in 161f5860c92a8ec80b6bdff16e79d70dcd8afc5a; From 3ff7ddb1353da9b535e65702704cbadea1da9a00 · fixed in 0ce42c7b84032335abff9eac43762e4ca8224451; From 3ff7ddb1353da9b535e65702704cbadea1da9a00 · fixed in 1c43f5db482f74b41987c39c9c375a5e767556eb; From 3ff7ddb1353da9b535e65702704cbadea1da9a00 · fixed in d313499df66159b4b7971d760d16729598ab7e5a

• Linux Linux

  5.8

• KernelLinux

  From 5.8.0 · fixed in 5.10.271; From 5.11.0 · fixed in 5.15.222; From 5.16.0 · fixed in 6.1.189; From 6.2.0 · fixed in 6.6.158; From 6.7.0 · fixed in 6.12.112; From 6.13.0 · fixed in 6.18.54; From 6.19.0 · fixed in 7.2.8

References 8