5.5

CVE-2026-64328: usb: gadget: f_fs: Fix DMA fence leak

Analyzed
AliasesUBUNTU-CVE-2026-64328DEBIAN-CVE-2026-64328
Published 25-07-2026Last modified 17-08-2026

Vulnerability summary

CVE-2026-64328 is a medium (CVSS 5.5) vulnerability in linux. EPSS estimates a 0.16% chance of exploitation in the next 30 days, higher than 5.3% of scored vulnerabilities.

Priority
Routine

Not severe (CVSS 5.5, local access); no exploitation reported by the 5 checked sources

Source freshness unavailable

How is this decided?
CVSS score
5.5/10
010
Medium · v3.1 (NVD)
EPSS score
0.16%
0%100%
Low · 0.00 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 17 · Related 17
OPENSUSE-SU-2026:11476-1OPENSUSE-SU-2026:21910-1SUSE-SU-2026:23881-1SUSE-SU-2026:23887-1SUSE-SU-2026:23897-1SUSE-SU-2026:23902-1

Timeline

  1. 25-07-2026
    PublishedVulnerability first disclosed.
  2. 17-08-2026
    Last modifiedVulnerability information updated.

Description

In the Linux kernel, the following vulnerability has been resolved: usb: gadget: f_fs: Fix DMA fence leak In ffs_dmabuf_transfer(), a ffs_dma_fence object is kmalloc'd, with the underlying dma_fence later initialized by dma_fence_init(), which sets its kref counter to 1. Then, dma_resv_add_fence() gets a second reference, and a pointer to the ffs_dma_fence is passed as the usb_request's "context" field. The dma-resv mechanism will manage the second reference, but the first reference is never properly released; the ffs_dmabuf_cleanup() function decreases the reference count, but only to balance with the reference grab in ffs_dmabuf_signal_done(). The code will then slowly leak memory as more ffs_dma_fence objects are created without being ever freed. Address this issue by transferring ownership of the fence to the DMA reservation object, by calling dma_fence_put() right after dma_resv_add_fence(). The ffs_dma_fence then gets properly discarded after being signalled.

CVSS metrics

3 scores · 3 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

No change 0.00 pp

From 0.16% 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

Affected systems

Version check

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

Ubuntu119 products
  • linux< 7.0.0-31.31
  • linux-allwinner-5.19All versions (No fix recorded)
  • linux-aws< 7.0.0-1012.12
  • linux-aws-5.0All versions (No fix recorded)
  • linux-aws-5.11All versions (No fix recorded)
Debian2 products
  • linux< 6.12.96-1 | < 7.1.4-1
  • linux-6.12< 6.12.100-1~deb12u1
Linux2 products
  • linux≥ 7b07a2a7ca02a20124b552be96c5a56910795488, < b7475b2dce5e121e687280ba5732ccefe77ffd2f | ≥ 7b07a2a7ca02a20124b552be96c5a56910795488, < e086c16962a1b0142e2675610e9c06fcfcd4c3a8 | ≥ 7b07a2a7ca02a20124b552be96c5a56910795488, < 0cae3d6109427c455bad0a18dfb3e2a91657e38a | ≥ 7b07a2a7ca02a20124b552be96c5a56910795488, < baa6b6068a3f2bf2ed525a1cb37975905dadc658 | 6.9
  • linux_kernel≥ 6.9, < 6.12.96 | ≥ 6.13, < 6.18.39 | ≥ 6.19, < 7.1.4 | 7.2:rc1 | 7.2:rc2

3 vendors · 123 products

References

19 links
Show all 19 references