Reference page — cumulative record through Wednesday, August 19, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.
Linux Linux — zsmalloc: fix races between asynchronous zspage free and page migration
AV AC PR UI S C I A CVSS EPSS %ile KEV
L H L N U N N H 4.7 .0022 12.4 —
AFFECTED
Product Versions Fixed
Linux 77ff465799c60294e248000cd22ae8171da3304c – —
Linux 4.14 – 4.14.282
TIMELINE
Feb 26 Reserved by Linux
Feb 26 Published (CNA: Linux)
Aug 4 RESCORED — CVE-2022-49554 (Linux). CVSS 7.8 → 4.7 (NVD).
Description
In the Linux kernel, the following vulnerability has been resolved:
zsmalloc: fix races between asynchronous zspage free and page migration
The asynchronous zspage free worker tries to lock a zspage's entire page
list without defending against page migration. Since pages which haven't
yet been locked can concurrently migrate off the zspage page list while
lock_zspage() churns away, lock_zspage() can suffer from a few different
lethal races.
It can lock a page which no longer belongs to the zspage and unsafely
dereference page_private(), it can unsafely dereference a torn pointer to
the next page (since there's a data race), and it can observe a spurious
NULL pointer to the next page and thus not lock all of the zspage's pages
(since a single page migration will reconstruct the entire page list, and
create_page_chain() unconditionally zeroes out each list pointer in the
process).
Fix the races by using migrate_read_lock() in lock_zspage() to synchronize
with page migration.
Lifecycle
Complete event history — 3 events, chronological
| Date | Event | Detail |
| February 26, 2025 | Reserved | Reserved by Linux |
| February 26, 2025 | Published | Published (CNA: Linux) |
| August 4, 2026 | RESCORED | RESCORED — CVE-2022-49554 (Linux). CVSS 7.8 → 4.7 (NVD). |
Affected
Affected products and packages — 2 rows
| Vendor | Product / Package | Ecosystem | Version introduced | Fixed |
| Linux | Linux | — | 77ff465799c60294e248000cd22ae8171da3304c | — |
| Linux | Linux | — | 4.14 | 4.14.282 |
About this page
This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2022-49554 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Wednesday, August 19, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.