{"id":"CVE-2025-68725","title":"bpf: Do not let BPF test infra emit invalid GSO types to stack","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Do not let BPF test infra emit invalid GSO types to stack\n\nYinhao et al. reported that their fuzzer tool was able to trigger a\nskb_warn_bad_offload() from netif_sk…","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= 850a88cc4096fe1df407452ba2e4d28cf5b3eee9 < bb7902ed7d7f6d6a7c6c4dc25410d6127ce1085f","Linux >= 850a88cc4096fe1df407452ba2e4d28cf5b3eee9 < e0ffb64a2d72c6705b4a4c9efef600409f7e98a0","Linux >= 850a88cc4096fe1df407452ba2e4d28cf5b3eee9 < 768376ece7036ecb8604961793a1b72afe6345dd","Linux >= 850a88cc4096fe1df407452ba2e4d28cf5b3eee9 < 8670b53b8ee91f028f7240531064020b7413c461","Linux >= 850a88cc4096fe1df407452ba2e4d28cf5b3eee9 < 0f3a60869ca22024dfb9c6fce412b0c70cb4ea36","Linux >= 850a88cc4096fe1df407452ba2e4d28cf5b3eee9 < fbea4c63b5385588cb44ab21f91e55e33c719a54","Linux >= 850a88cc4096fe1df407452ba2e4d28cf5b3eee9 < 04a899573fb87273a656f178b5f920c505f68875","Linux 5.6"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"partial","timestamp":"2026-06-10T20:40:17.204014Z"},"published":"2025-12-24","updated":"2026-09-08","sourceUpdated":"2026-09-08T08:43:20.254Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2025-68725","references":[{"url":"https://git.kernel.org/stable/c/bb7902ed7d7f6d6a7c6c4dc25410d6127ce1085f"},{"url":"https://git.kernel.org/stable/c/e0ffb64a2d72c6705b4a4c9efef600409f7e98a0"},{"url":"https://git.kernel.org/stable/c/768376ece7036ecb8604961793a1b72afe6345dd"},{"url":"https://git.kernel.org/stable/c/8670b53b8ee91f028f7240531064020b7413c461"},{"url":"https://git.kernel.org/stable/c/0f3a60869ca22024dfb9c6fce412b0c70cb4ea36"},{"url":"https://git.kernel.org/stable/c/fbea4c63b5385588cb44ab21f91e55e33c719a54"},{"url":"https://git.kernel.org/stable/c/04a899573fb87273a656f178b5f920c505f68875"}],"tags":["cve.org"],"epss":0.00181,"epssPercentile":0.0675,"ingestedAt":"2026-09-08T15:33:26.995Z","slug":"CVE-2025-68725","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Do not let BPF test infra emit invalid GSO types to stack\n\nYinhao et al. reported that their fuzzer tool was able to trigger a\nskb_warn_bad_offload() from netif_skb_features() -> gso_features_check().\nWhen a BPF program - triggered via BPF test infra - pushes the packet\nto the loopback device via bpf_clone_redirect() then mentioned offload\nwarning can be seen. GSO-related features are then rightfully disabled.\n\nWe get into this situation due to convert___skb_to_skb() setting\ngso_segs and gso_size but not gso_type. Technically, it makes sense\nthat this warning triggers since the GSO properties are malformed due\nto the gso_type. Potentially, the gso_type could be marked non-trustworthy\nthrough setting it at least to SKB_GSO_DODGY without any other specific\nassumptions, but that also feels wrong given we should not go further\ninto the GSO engine in the first place.\n\nThe checks were added in 121d57af308d (\"gso: validate gso_type in GSO\nhandlers\") because there were malicious (syzbot) senders that combine\na protocol with a non-matching gso_type. If we would want to drop such\npackets, gso_features_check() currently only returns feature flags via\nnetif_skb_features(), so one location for potentially dropping such skbs\ncould be validate_xmit_unreadable_skb(), but then otoh it would be\nan additional check in the fast-path for a very corner case. Given\nbpf_clone_redirect() is the only place where BPF test infra could emit\nsuch packets, lets reject them right there.\n\n## Affected\n\n- `Linux >= 850a88cc4096fe1df407452ba2e4d28cf5b3eee9 < bb7902ed7d7f6d6a7c6c4dc25410d6127ce1085f`\n- `Linux >= 850a88cc4096fe1df407452ba2e4d28cf5b3eee9 < e0ffb64a2d72c6705b4a4c9efef600409f7e98a0`\n- `Linux >= 850a88cc4096fe1df407452ba2e4d28cf5b3eee9 < 768376ece7036ecb8604961793a1b72afe6345dd`\n- `Linux >= 850a88cc4096fe1df407452ba2e4d28cf5b3eee9 < 8670b53b8ee91f028f7240531064020b7413c461`\n- `Linux >= 850a88cc4096fe1df407452ba2e4d28cf5b3eee9 < 0f3a60869ca22024dfb9c6fce412b0c70cb4ea36`\n- `Linux >= 850a88cc4096fe1df407452ba2e4d28cf5b3eee9 < fbea4c63b5385588cb44ab21f91e55e33c719a54`\n- `Linux >= 850a88cc4096fe1df407452ba2e4d28cf5b3eee9 < 04a899573fb87273a656f178b5f920c505f68875`\n- `Linux 5.6`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}