Answer in brief
CVE-2026-74321 records a High severity (CVSS 7.5) vulnerability in btrfs: fix invalid pointer dereference in __btrfs_run_delayed_refs(). 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 7.5. 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 | >=0110a4c43451533de1ea1bbdc57b5d452f9d8b25 <c372ca227e16bace86f1df1fa4ae6849e2fcfa28 || >=0110a4c43451533de1ea1bbdc57b5d452f9d8b25 <a71143590ce9764dbcb47617647592ff8b4d48bc || >=0110a4c43451533de1ea1bbdc57b5d452f9d8b25 <65770111a2d47c2b15e20b2ba92bb12198f289d4 || >=0110a4c43451533de1ea1bbdc57b5d452f9d8b25 <015dc4a1e0c2cba551d4620eba13d26d5081dc34 || >=0110a4c43451533de1ea1bbdc57b5d452f9d8b25 <ba9fa2ff5981589bb49094d3358c339b37c47f53 || >=0110a4c43451533de1ea1bbdc57b5d452f9d8b25 <3b15d02be05e74321adb1e0ae0cb4ccfba7c6cb1 || >=0110a4c43451533de1ea1bbdc57b5d452f9d8b25 <9faa6b69ad73f03c7bde53e07d75a28822dc9a1a || >=0110a4c43451533de1ea1bbdc57b5d452f9d8b25 <486f8298b6188ff11ef1f4be7f1d5d2e4d1b1fae | c372ca227e16bace86f1df1fa4ae6849e2fcfa28, a71143590ce9764dbcb47617647592ff8b4d48bc, 65770111a2d47c2b15e20b2ba92bb12198f289d4, 015dc4a1e0c2cba551d4620eba13d26d5081dc34, ba9fa2ff5981589bb49094d3358c339b37c47f53, 3b15d02be05e74321adb1e0ae0cb4ccfba7c6cb1, 9faa6b69ad73f03c7bde53e07d75a28822dc9a1a, 486f8298b6188ff11ef1f4be7f1d5d2e4d1b1fae |
| Linux/Linuxgeneric | 4.20 | Not reported |
Published upstream
Aug 15, 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 15, 2026
In the Linux kernel, the following vulnerability has been resolved: btrfs: fix invalid pointer dereference in __btrfs_run_delayed_refs() In the beginning of the loop, we try to obtain a locked delayed ref head, if 'locked_ref' is currently NULL, by calling btrfs_select_ref_head(), which can return an error pointer. If the error pointer is -EAGAIN we do a continue and go back to the beginning of the loop, which will not try again to call btrfs_select_ref_head() since 'locked_ref' is no longer NULL but it's ERR_PTR(-EAGAIN), and then we do: spin_lock(&locked_ref->lock); against a ERR_PTR(-EAGAIN) value, generating an invalid pointer dereference. Fix this by ensuring that 'locked_ref' is set to NULL when btrfs_select_ref_head() returns ERR_PTR(-EAGAIN) and incrementing 'count' as well, to prevent infinite looping. We do this by doing a goto to the bottom of the loop that already sets 'locked_ref' to NULL and does a cond_resched(), with an increment to 'count' right before the goto. These measures were in place before the refactoring in commit 0110a4c43451 ("btrfs: refactor __btrfs_run_delayed_refs loop") but were unintentionally lost afterwards.
Quoted source text, attributed separately from HOL analysis.