4.7

CVE-2025-38448: usb: gadget: u_serial: Fix race condition in TTY wakeup

Analyzed
AliasesUBUNTU-CVE-2025-38448DEBIAN-CVE-2025-38448
Published 25-07-2025Last modified 11-05-2026

Vulnerability summary

CVE-2025-38448 is a medium (CVSS 4.7) vulnerability in debian debian_linux. EPSS estimates a 0.14% chance of exploitation in the next 30 days, higher than 3.4% of scored vulnerabilities.

Priority
Routine

Not severe (CVSS 4.7, local access); no exploitation reported by the 5 checked sources

Source freshness unavailable

How is this decided?
CVSS score
4.7/10
010
Medium · v3.1 (NVD)
EPSS score
0.14%
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 53 · Related 47
DLA-4327-1DLA-4328-1DSA-5973-1DSA-5975-1MGASA-2025-0218MGASA-2025-0219

Timeline

  1. 25-07-2025
    PublishedVulnerability first disclosed.
  2. 11-05-2026
    Last modifiedVulnerability information updated.

Description

In the Linux kernel, the following vulnerability has been resolved: usb: gadget: u_serial: Fix race condition in TTY wakeup A race condition occurs when gs_start_io() calls either gs_start_rx() or gs_start_tx(), as those functions briefly drop the port_lock for usb_ep_queue(). This allows gs_close() and gserial_disconnect() to clear port.tty and port_usb, respectively. Use the null-safe TTY Port helper function to wake up TTY. Example CPU1: CPU2: gserial_connect() // lock gs_close() // await lock gs_start_rx() // unlock usb_ep_queue() gs_close() // lock, reset port.tty and unlock gs_start_rx() // lock tty_wakeup() // NPE

CVSS metrics

4 scores · 3 sources · 2 versions

EPSS trend

Probability

0.14%

Chance of exploitation in the next 30 days

Percentile

3%

Versus all other CVEs

30-day change

Increase +0.02 pp

From 0.12% 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.

Ubuntu147 products
  • linuxAll versions (No fix recorded) | < 5.15.0-156.166 | < 6.8.0-100.100
  • linux-allwinner-5.19All versions (No fix recorded)
  • linux-awsAll versions (No fix recorded) | < 5.15.0-1092.99 | < 6.8.0-1046.49
  • linux-aws-5.0All versions (No fix recorded)
  • linux-aws-5.11All versions (No fix recorded)
Debian2 products
  • linux< 6.1.147-1 | < 6.12.41-1 | < 6.16.3-1
  • debian_linuxEOL11.0
Linux2 products
  • linux≥ 35f95fd7f234d2b58803bab6f6ebd6bb988050a2, < 18d58a467ccf011078352d91b4d6a0108c7318e8 | ≥ 35f95fd7f234d2b58803bab6f6ebd6bb988050a2, < d43657b59f36e88289a6066f15bc9a80df5014eb | ≥ 35f95fd7f234d2b58803bab6f6ebd6bb988050a2, < a5012673d49788f16bb4e375b002d7743eb642d9 | ≥ 35f95fd7f234d2b58803bab6f6ebd6bb988050a2, < ee8d688e2ba558f3bb8ac225113740be5f335417 | ≥ 35f95fd7f234d2b58803bab6f6ebd6bb988050a2, < c6eb4a05af3d0ba3bc4e8159287722fb9abc6359 | ≥ 35f95fd7f234d2b58803bab6f6ebd6bb988050a2, < abf3620cba68e0e51e5c21054ce4f925f75b3661 | ≥ 35f95fd7f234d2b58803bab6f6ebd6bb988050a2, < c8c80a3a35c2e3488409de2d5376ef7e662a2bf5 | ≥ 35f95fd7f234d2b58803bab6f6ebd6bb988050a2, < c529c3730bd09115684644e26bf01ecbd7e2c2c9 | 3.5
  • linux_kernel≥ 3.5, < 5.4.296 | ≥ 5.5, < 5.10.240 | ≥ 5.11, < 5.15.189 | ≥ 5.16, < 6.1.146 | ≥ 6.2, < 6.6.99 | ≥ 6.7, < 6.12.39 | ≥ 6.13, < 6.15.7 | 6.16:rc1 | 6.16:rc2 | 6.16:rc3 | 6.16:rc4

3 vendors · 151 products

References

46 links
Show all 46 references