Answer in brief
CVE-2026-80550 records a High severity (CVSS 7.9) vulnerability in s390/vfio_ccw: Fix out of bounds check on CCW array. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 7.9. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=0a19e61e6d4c6192077ead760ba0a2d350987d4c <0282fb1c4b638eecfe2cc558092c460911d8f7e2 || >=0a19e61e6d4c6192077ead760ba0a2d350987d4c <907adc667d902fafbdb2d740d57b55bd025dc4cd || >=0a19e61e6d4c6192077ead760ba0a2d350987d4c <f20be33d093ce7630c17ff7ed93caf7eaf8ac1a3 || >=0a19e61e6d4c6192077ead760ba0a2d350987d4c <af3f80ca4c8b17f20f9e588def076288fdb49e65 || >=0a19e61e6d4c6192077ead760ba0a2d350987d4c <499a8a66b1598bfab97182aed15e0f1646074a3d || >=0a19e61e6d4c6192077ead760ba0a2d350987d4c <4c2e1d359d7a2b82cdf3254e4e480af9417f99fb || >=0a19e61e6d4c6192077ead760ba0a2d350987d4c <d5d096cd9369e986d4e5153baa86b8b35c283e09 || >=0a19e61e6d4c6192077ead760ba0a2d350987d4c <a005b7f1a491ffda61bff0fd0f6548f8986fb977 | 0282fb1c4b638eecfe2cc558092c460911d8f7e2, 907adc667d902fafbdb2d740d57b55bd025dc4cd, f20be33d093ce7630c17ff7ed93caf7eaf8ac1a3, af3f80ca4c8b17f20f9e588def076288fdb49e65, 499a8a66b1598bfab97182aed15e0f1646074a3d, 4c2e1d359d7a2b82cdf3254e4e480af9417f99fb, d5d096cd9369e986d4e5153baa86b8b35c283e09, a005b7f1a491ffda61bff0fd0f6548f8986fb977 |
| Linux/Linuxgeneric | 4.12 | Not reported |
Published upstream
Aug 26, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 27, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 26, 2026
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.
Quoted source text, attributed separately from HOL analysis.