{"id":"CVE-2026-43238","title":"net/sched: act_skbedit: fix divide-by-zero in tcf_skbedit_hash()","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: act_skbedit: fix divide-by-zero in tcf_skbedit_hash()\n\nCommit 38a6f0865796 (\"net: sched: support hash selecting tx queue\")\nadded SKBEDIT_F_TXQ_SKBHASH suppor…","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= 38a6f0865796e26fc38fff4858f681d9ae76fa0f < 59809fda4da7730cfe84a948033f47eb45db073d","Linux >= 38a6f0865796e26fc38fff4858f681d9ae76fa0f < 9c735a7d98c982a786b0db71eb6566ee00aaa04f","Linux >= 38a6f0865796e26fc38fff4858f681d9ae76fa0f < 015cebdfcb97b5347fb7f598ea712a281cb35840","Linux >= 38a6f0865796e26fc38fff4858f681d9ae76fa0f < 4ece5eb4836f8ff03b9004dc2430a7169f282851","Linux >= 38a6f0865796e26fc38fff4858f681d9ae76fa0f < 3c2b95b26860bd6f8e2310d31ea1200d3f8f173e","Linux >= 38a6f0865796e26fc38fff4858f681d9ae76fa0f < be054cc66f739a9ba615dba9012a07fab8e7dd6f","Linux 5.19"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"partial","timestamp":"2026-11-06T15:31:06.549256Z"},"published":"2026-05-06","updated":"2026-11-06","sourceUpdated":"2026-11-06T15:32:36.828Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-43238","references":[{"url":"https://git.kernel.org/stable/c/59809fda4da7730cfe84a948033f47eb45db073d"},{"url":"https://git.kernel.org/stable/c/9c735a7d98c982a786b0db71eb6566ee00aaa04f"},{"url":"https://git.kernel.org/stable/c/015cebdfcb97b5347fb7f598ea712a281cb35840"},{"url":"https://git.kernel.org/stable/c/4ece5eb4836f8ff03b9004dc2430a7169f282851"},{"url":"https://git.kernel.org/stable/c/3c2b95b26860bd6f8e2310d31ea1200d3f8f173e"},{"url":"https://git.kernel.org/stable/c/be054cc66f739a9ba615dba9012a07fab8e7dd6f"}],"tags":["cve.org"],"epss":0.00128,"epssPercentile":0.02474,"ingestedAt":"2026-11-06T15:54:04.006Z","slug":"CVE-2026-43238","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: act_skbedit: fix divide-by-zero in tcf_skbedit_hash()\n\nCommit 38a6f0865796 (\"net: sched: support hash selecting tx queue\")\nadded SKBEDIT_F_TXQ_SKBHASH support. The inclusive range size is\ncomputed as:\n\nmapping_mod = queue_mapping_max - queue_mapping + 1;\n\nThe range size can be 65536 when the requested range covers all possible\nu16 queue IDs (e.g. queue_mapping=0 and queue_mapping_max=U16_MAX).\nThat value cannot be represented in a u16 and previously wrapped to 0,\nso tcf_skbedit_hash() could trigger a divide-by-zero:\n\nqueue_mapping += skb_get_hash(skb) % params->mapping_mod;\n\nCompute mapping_mod in a wider type and reject ranges larger than U16_MAX\nto prevent params->mapping_mod from becoming 0 and avoid the crash.\n\n## Affected\n\n- `Linux >= 38a6f0865796e26fc38fff4858f681d9ae76fa0f < 59809fda4da7730cfe84a948033f47eb45db073d`\n- `Linux >= 38a6f0865796e26fc38fff4858f681d9ae76fa0f < 9c735a7d98c982a786b0db71eb6566ee00aaa04f`\n- `Linux >= 38a6f0865796e26fc38fff4858f681d9ae76fa0f < 015cebdfcb97b5347fb7f598ea712a281cb35840`\n- `Linux >= 38a6f0865796e26fc38fff4858f681d9ae76fa0f < 4ece5eb4836f8ff03b9004dc2430a7169f282851`\n- `Linux >= 38a6f0865796e26fc38fff4858f681d9ae76fa0f < 3c2b95b26860bd6f8e2310d31ea1200d3f8f173e`\n- `Linux >= 38a6f0865796e26fc38fff4858f681d9ae76fa0f < be054cc66f739a9ba615dba9012a07fab8e7dd6f`\n- `Linux 5.19`\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":[]}