7.8

CVE-2026-64532: linux Out-of-bounds Write

CVSS: 7.8v3.1HighReceived
AliasesUBUNTU-CVE-2026-64532DEBIAN-CVE-2026-64532
Published 27-07-2026Last modified 19-10-2026
Open JSON

Vulnerability summary

CVE-2026-64532 is a high (CVSS 7.8) Out-of-bounds Write vulnerability in linux. EPSS estimates a 0.13% chance of exploitation in the next 30 days, higher than 2.2% of scored vulnerabilities.

Overall risk
31/100
0100
Medium · default modelHow is this calculated?
CVSS score
7.8/10
010
High · v3.1 (CVE.org)
EPSS score
0.13%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 18 · Related 16
MGASA-2026-0336MGASA-2026-0337OPENSUSE-SU-2026:11476-1USN-8875-1USN-8875-2USN-8876-1

Timeline

  1. 27-07-2026
    PublishedVulnerability first disclosed.
  2. 19-10-2026
    Last modifiedVulnerability information updated.

Description

In the Linux kernel, the following vulnerability has been resolved: fs/ntfs3: bound NTFS_DE view.data_off in UpdateRecordData{Root,Allocation} In do_action()'s UpdateRecordDataRoot (fslog.c:3489) and UpdateRecordDataAllocation (fslog.c:3697) cases, the memmove destination is `Add2Ptr(e, le16_to_cpu(e->view.data_off))`, where e->view.data_off comes from an on-disk NTFS_DE inside an INDEX_ROOT or INDEX_BUFFER. Neither case validates view.data_off + dlen against e->size; the existing check_if_index_root / check_if_alloc_index helpers walk the entry chain and validate the entry's offset, but not its internal view fields. The neighbouring read sites (e.g., fs/ntfs3/index.c when iterating view entries) check view.data_off + view.data_size <= e->size. Apply the same bound at the two memmove sites. Reproduced under UML+KASAN on mainline 8d90b09e6741 via pr_warn-only probe instrumentation: with view.data_off forced to 0xFFFC, the memmove writes 32 bytes past the end of the NTFS_DE. This is similar in shape to Pavitra Jha's 2026-05-02 patch "fs/ntfs3: prevent oob in case UpdateRecordDataRoot" (<20260502105008.21827-1-jhapavitra98@gmail.com>) which proposes calling ntfs3_bad_de_range(); that helper does not exist in mainline. This patch uses inline checks.

CVSS metrics

5 scores · 4 sources · 2 versions

EPSS trend

Probability

0.13%

Chance of exploitation in the next 30 days

Percentile

2%

Versus all other CVEs

30-day change

0.00 pp

From 0.13% on 19-09-2026

19-09-202619-10-2026
EPSS score
0.13%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Ubuntu157 products
  • linuxAll versions (No fix recorded) | < 5.15.0-198.208 | < 6.8.0-147.147 | < 7.0.0-38.38
  • linux-allwinner-5.19All versions (No fix recorded)
  • linux-awsAll versions (No fix recorded) | < 5.15.0-1117.124 | < 6.8.0-1067.70 | < 7.0.0-1014.14
  • linux-aws-5.0All versions (No fix recorded)
  • linux-aws-5.11All versions (No fix recorded)
Debian2 products
  • linux< 6.1.180-1 | < 6.12.100-1 | < 7.1.5-1
  • linux-6.12< 6.12.100-1~deb12u1
Linux1 product
  • linux≥ b46acd6a6a627d876898e1c84d3f84902264b445, < b20e5a709d8bd190d6e4645606763c7423e694c1 | ≥ b46acd6a6a627d876898e1c84d3f84902264b445, < d41b382068ca4e64e421f736cdd700095464b6ac | ≥ b46acd6a6a627d876898e1c84d3f84902264b445, < 429d653ca641d38a78609b8f62e81a0a5c780a2d | ≥ b46acd6a6a627d876898e1c84d3f84902264b445, < 315d3a9a48b49f889da3d858a9307e677cb9e1bd | ≥ b46acd6a6a627d876898e1c84d3f84902264b445, < be306b8d9143a9c076c804a7ca025d69caf9c448 | ≥ b46acd6a6a627d876898e1c84d3f84902264b445, < 36feda687afebae24c472202694448738809c411 | ≥ b46acd6a6a627d876898e1c84d3f84902264b445, < 3e127829e57f5190f612412ece4541cb96d5ec7a | 5.15

3 vendors · 160 products

References

27 links
Show all 27 references