Answer in brief
CVE-2026-63817 records a High severity (CVSS 7.8) vulnerability in f2fs: validate compress cache inode only when enabled. 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 7.8. 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 | >=6ce19aff0b8cd386860855185c6cd79337fc4d2b <fcc051d377a9701a452e7663a1a8223c26225df9 || >=6ce19aff0b8cd386860855185c6cd79337fc4d2b <29115b8c9172d34e67ab26cc4f6c209b7a236d7a || >=6ce19aff0b8cd386860855185c6cd79337fc4d2b <13e4b59d3a9413f66f116fa6c4828519b960a5ea || >=6ce19aff0b8cd386860855185c6cd79337fc4d2b <16161444c30d8dff9428abbae42b72ce4e32a932 || >=6ce19aff0b8cd386860855185c6cd79337fc4d2b <77f216ff9ce5cde8eed9f6d12707e906dffdc9f7 || >=6ce19aff0b8cd386860855185c6cd79337fc4d2b <0969926d987bbde9a1aa49da317582ba37095805 || >=6ce19aff0b8cd386860855185c6cd79337fc4d2b <5073c66a96a9c23c0c2533ed4ed06e42f9021208 || a23706426da9b611be5beae0f3faa260fb453b4e || >=5.13.19 <5.14 | fcc051d377a9701a452e7663a1a8223c26225df9, 29115b8c9172d34e67ab26cc4f6c209b7a236d7a, 13e4b59d3a9413f66f116fa6c4828519b960a5ea, 16161444c30d8dff9428abbae42b72ce4e32a932, 77f216ff9ce5cde8eed9f6d12707e906dffdc9f7, 0969926d987bbde9a1aa49da317582ba37095805, 5073c66a96a9c23c0c2533ed4ed06e42f9021208, 5.14 |
| Linux/Linuxgeneric | 5.14 | Not reported |
Published upstream
Jul 19, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 17, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 5, 2026
In the Linux kernel, the following vulnerability has been resolved: f2fs: validate compress cache inode only when enabled F2FS_COMPRESS_INO() uses NM_I(sbi)->max_nid as the synthetic inode number for the compressed page cache inode. That inode only exists when the compress_cache mount option is enabled. When compress_cache is disabled, max_nid is outside the valid inode range. A corrupted directory entry that points to ino == max_nid should therefore be rejected by f2fs_check_nid_range(). However, is_meta_ino() currently treats F2FS_COMPRESS_INO() as a meta inode unconditionally, so f2fs_iget() bypasses do_read_inode() and its nid range check, and instantiates a fake internal inode instead. Gate the compressed cache inode case on COMPRESS_CACHE, matching f2fs_init_compress_inode(). With compress_cache disabled, ino == max_nid now follows the normal inode path and is rejected as an out-of-range nid.
Quoted source text, attributed separately from HOL analysis.