{"apiVersion":"1.0","identifier":"CVE-2026-80550","description":"In the Linux kernel, the following vulnerability has been resolved: s390/vfio_ccw: Fix out of bounds check on CCW array The routine ccwchain_calc_length() counts the number of channel command words (CCWs) that are chained together in a single channel program, and rejects anything larger than CCWCHAIN_LEN_MAX (256) CCWs. The loop itself is -do..while (count < 257)-, and while the logic in is_cpa_within_range() correctly adjusts between the 0-index array of CCWs and the count of CCWs starting at 1, this means it would look at a possible 257th CCW before ending the loop and (correctly) returning an error. Fix this by restructuring the loop to break as soon as 256 CCWs (thus indexes 0-255) are examined, without looking at memory outside the range.","publishedAt":"2026-08-26T15:17:09","lastModifiedAt":"2026-08-27T06:17:37","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-80550","cvssScore":7.9,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:L","epssProbability":0.00137,"riskScore":0.8,"affectedProduct":"Linux kernel","affectedVersions":"unknown","vulnerabilityType":"Kernel","operatingSystems":[],"links":{"self":"https://www.redsauce.net/api/cves/CVE-2026-80550","webPages":{"es":"https://www.redsauce.net/es/cves/CVE-2026-80550","en":"https://www.redsauce.net/en/cves/CVE-2026-80550","fr":"https://www.redsauce.net/fr/cves/CVE-2026-80550","pt":"https://www.redsauce.net/pt/cves/CVE-2026-80550","de":"https://www.redsauce.net/de/cves/CVE-2026-80550","sk":"https://www.redsauce.net/sk/cves/CVE-2026-80550","el":"https://www.redsauce.net/el/cves/CVE-2026-80550"},"source":"https://nvd.nist.gov/vuln/detail/CVE-2026-80550"}}