{"apiVersion":"1.0","identifier":"CVE-2026-99274","description":"In the Linux kernel, the following vulnerability has been resolved: smb: client: fix fiemap wild read on empty truncated response smb3_fiemap() treats -E2BIG from SMB2_ioctl() as a truncated range blob and loops for the next chunk. If the server reports STATUS_BUFFER_OVERFLOW with OutputCount == 0, SMB2_ioctl() returns -E2BIG with out_data == NULL and out_data_len == 0, and the existing length checks accept the empty result. The loop then evaluates next = out_data[num - 1].file_offset + ... with num == 0, reading 16 bytes before NULL. Reject a truncated range blob that contains no range, so the resume offset is never computed from an empty response. Also require the last range in a truncated blob to advance the resume offset without overflowing, and to stay within the requested range; a malicious or broken server could otherwise make no progress or underflow len and loop forever. Free the previous response buffer before retrying. Reproduced on 6.6.87.2 with a malicious SMB2 server that answers FSCTL_QUERY_ALLOCATED_RANGES with STATUS_BUFFER_OVERFLOW and OutputCount == 0; an FS_IOC_FIEMAP ioctl on the mount oopses in cifs_fiemap() with CR2 = fffffffffffffff8. The code path is unchanged on mainline.","publishedAt":"2026-11-07T14:17:02","lastModifiedAt":"2026-11-10T19:22:31","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-99274","cvssScore":null,"cvssVector":null,"epssProbability":0.00157,"riskScore":null,"affectedProduct":"Linux kernel","affectedVersions":"unknown","vulnerabilityType":"Kernel","operatingSystems":[],"links":{"self":"https://www.redsauce.net/api/cves/CVE-2026-99274","webPages":{"es":"https://www.redsauce.net/es/cves/CVE-2026-99274","en":"https://www.redsauce.net/en/cves/CVE-2026-99274","fr":"https://www.redsauce.net/fr/cves/CVE-2026-99274","pt":"https://www.redsauce.net/pt/cves/CVE-2026-99274","de":"https://www.redsauce.net/de/cves/CVE-2026-99274","sk":"https://www.redsauce.net/sk/cves/CVE-2026-99274","el":"https://www.redsauce.net/el/cves/CVE-2026-99274"},"source":"https://nvd.nist.gov/vuln/detail/CVE-2026-99274"}}