{"apiVersion":"1.0","identifier":"CVE-2026-72111","description":"In the Linux kernel, the following vulnerability has been resolved: bpf: Reset register bounds before narrowing retval range in check_mem_access() When the BPF verifier processes a context load of an LSM hook return value, it calls __mark_reg_s32_range() to narrow the register to the hook-s valid range. However, __mark_reg_s32_range() intersects the new range with the register-s existing bounds using max_t()/min_t() rather than replacing them. If the destination register carries stale bounds from a prior instruction (e.g. BPF_MOV64_IMM), the intersection can produce a range narrower than reality. The verifier then believes it knows the register-s exact value, while at runtime the actual hook return value is loaded, creating a verifier/runtime mismatch that can be used to bypass BPF memory safety checks. The else branch already calls mark_reg_unknown() to reset register state before any narrowing. Apply the same reset in the is_retval path so stale bounds are cleared before __mark_reg_s32_range() intersects.","publishedAt":"2026-08-15T06:21:25","lastModifiedAt":"2026-08-17T06:18:10","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-72111","cvssScore":8.8,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H","epssProbability":0.00176,"riskScore":0.89,"affectedProduct":"Linux kernel","affectedVersions":"unknown","vulnerabilityType":"Kernel","operatingSystems":[],"links":{"self":"https://www.redsauce.net/api/cves/CVE-2026-72111","webPages":{"es":"https://www.redsauce.net/es/cves/CVE-2026-72111","en":"https://www.redsauce.net/en/cves/CVE-2026-72111","fr":"https://www.redsauce.net/fr/cves/CVE-2026-72111","pt":"https://www.redsauce.net/pt/cves/CVE-2026-72111","de":"https://www.redsauce.net/de/cves/CVE-2026-72111","sk":"https://www.redsauce.net/sk/cves/CVE-2026-72111","el":"https://www.redsauce.net/el/cves/CVE-2026-72111"},"source":"https://nvd.nist.gov/vuln/detail/CVE-2026-72111"}}