{"apiVersion":"1.0","identifier":"CVE-2026-72367","description":"In the Linux kernel, the following vulnerability has been resolved: iomap: guard io_size EOF trim against concurrent truncate underflow iomap: fix zero padding data issue in concurrent append writes changed ioend accounting so that io_size tracks only valid data within EOF. This trims io_size when a writeback range extends past end_pos: ioend->io_size += map_len; if (ioend->io_offset + ioend->io_size > end_pos) ioend->io_size = end_pos - ioend->io_offset; However, if end_pos ends up below ioend->io_offset, the subtraction becomes negative and is stored in size_t io_size, causing an unsigned wrap to a huge value. This can happen when writeback continues past byte-level EOF up to a block-aligned range, or when a concurrent truncate shrinks the file after end_pos was sampled in iomap_writeback_handle_eof(). A wrapped io_size can mislead append detection and corrupt completion-time size handling, since filesystem end_io paths consume io_size for decisions such as on-disk EOF updates and unwritten/COW completion ranges. Fix this by clamping io_size to zero when EOF has moved to or before the ioend start offset. This preserves the original intent of trimming io_size to valid in-EOF data while avoiding the underflow.","publishedAt":"2026-08-15T06:22:10","lastModifiedAt":"2026-08-17T06:18:40","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-72367","cvssScore":8.8,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","epssProbability":0.00582,"riskScore":0.93,"affectedProduct":"Linux kernel","affectedVersions":"unknown","vulnerabilityType":"Kernel","operatingSystems":[],"links":{"self":"https://www.redsauce.net/api/cves/CVE-2026-72367","webPages":{"es":"https://www.redsauce.net/es/cves/CVE-2026-72367","en":"https://www.redsauce.net/en/cves/CVE-2026-72367","fr":"https://www.redsauce.net/fr/cves/CVE-2026-72367","pt":"https://www.redsauce.net/pt/cves/CVE-2026-72367","de":"https://www.redsauce.net/de/cves/CVE-2026-72367","sk":"https://www.redsauce.net/sk/cves/CVE-2026-72367","el":"https://www.redsauce.net/el/cves/CVE-2026-72367"},"source":"https://nvd.nist.gov/vuln/detail/CVE-2026-72367"}}