7.8

CVE-2026-89755: mm/migrate_device: clear stale mapping after freeing swapcache

Received
AliasesUBUNTU-CVE-2026-89755DEBIAN-CVE-2026-89755
Published 11-09-2026Last modified 21-10-2026

Vulnerability summary

CVE-2026-89755 is a high (CVSS 7.8) vulnerability in linux. EPSS estimates a 0.16% chance of exploitation in the next 30 days, higher than 4.8% of scored vulnerabilities.

Priority
Routine

Not severe (CVSS 7.8, local access); no exploitation reported by the 5 checked sources

Source freshness unavailable

How is this decided?
CVSS score
7.8/10
010
High · v3.1 (CVE.org)
EPSS score
0.16%
0%100%
Low · -0.02 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 6 · Related 6

Timeline

  1. 11-09-2026
    PublishedVulnerability first disclosed.
  2. 21-10-2026
    Last modifiedVulnerability information updated.

Description

In the Linux kernel, the following vulnerability has been resolved: mm/migrate_device: clear stale mapping after freeing swapcache __migrate_device_pages() reads the folio mapping before calling folio_free_swap(). When folio_free_swap() succeeds, the folio is removed from the swap cache, but the saved mapping still points to swap_space. Passing the stale mapping to folio_migrate_mapping() makes it use the mapped-folio path for a folio that is no longer in swapcache. It can then operate on swap_space.i_pages with invalid reference accounting, eventually triggering a folio reference count BUG. After a successful split, nr still contains the number of pages in the original large folio, although each resulting page is now a separate order-0 folio. Reset nr to 1 so each split folio is processed separately, including its own swapcache removal and mapping lookup. Refresh the saved mapping after folio_free_swap() so the current folio state is used during migration.

CVSS metrics

4 scores · 4 sources · 1 version

EPSS trend

Probability

0.16%

Chance of exploitation in the next 30 days

Percentile

5%

Versus all other CVEs

30-day change

Decrease -0.02 pp

From 0.17% on 04-10-2026

04-10-202603-11-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

No weakness data has been published for this record.

Affected systems

Version check

Known conditions: local access, low-privilege account, no user interaction (CVSS vector). Other conditions: not stated in public data.

Ubuntu142 products
  • linuxAll versions (No fix recorded)
  • linux-allwinner-5.19All versions (No fix recorded)
  • linux-awsAll versions (No fix recorded)
  • linux-aws-5.0All versions (No fix recorded)
  • linux-aws-5.11All versions (No fix recorded)
Debian2 products
  • linux< 6.12.111-1 | < 7.2.6-1
  • linux-6.12< 6.12.111-1~deb12u1
Linux1 product
  • linux≥ df263d9a7dffee94ca5391120ee3b0587efa07f1, < 92db780dd644590c751246187e1229d5ac2e5544 | ≥ df263d9a7dffee94ca5391120ee3b0587efa07f1, < 4fa91f7bbc4135240b67daac03fc17d9e180a331 | ≥ df263d9a7dffee94ca5391120ee3b0587efa07f1, < 8ffedc6573a665cdc31ebe47eae7b32b78d0df83 | ≥ df263d9a7dffee94ca5391120ee3b0587efa07f1, < 34a00895d032a414830d41106a09329ae6c251b6 | 6.6

3 vendors · 145 products

References

8 links