CVE-2026-43061 | serial: 8250: Fix TX deadlock when using DMA

In the Linux kernel, the following vulnerability has been resolved: serial: 8250: Fix TX deadlock when using DMA `dmaengine_terminate_async` does not guarantee that the `__dma_tx_complete` callback will run. The callback is currently the only place where `dma->tx_running` gets cleared. If the transaction is canceled and the callback never runs, then `dma->tx_running` will never get cleared and we will never schedule new TX DMA transactions again. This change makes it so we clear `dma->tx_running` after we terminate the DMA transaction. This is "safe" because `serial8250_tx_dma_flush` is holding the UART port lock. The first thing the callback does is also grab the UART port lock, so access to `dma->tx_running` is serialized.

Published: 2026-05-05 Last update: 2026-06-17 Assigner: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-43061 is rated Low Risk (22.3/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.09%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-43061

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.02% 0.09% +0.07%
2 2026-05-06 — 0.02% —

Full EPSS history (2 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-43061

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.5 3.1 MEDIUM
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 1.8 3.6 [email protected]

Weakness enumeration for CVE-2026-43061

GitHub Security Advisory for CVE-2026-43061

GHSA-6grr-36f8-j7pv · Severity: medium — In the Linux kernel, the following vulnerability has been resolved: serial: 8250: Fix TX...

OS Trackers for CVE-2026-43061

vendor priority summary link
debian not yet assigned CVE-2026-43061 not yet assigned priority: Debian including 1 source packages (linux), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2026-43061
redhat medium — https://access.redhat.com/security/cve/CVE-2026-43061
suse — — https://www.suse.com/security/cve/CVE-2026-43061/
ubuntu medium CVE-2026-43061 medium priority: Ubuntu including 161 source packages (linux, linux-allwinner-5.19, …), 1449 status rows across 9 suites (bionic, focal, jammy, noble, questing, resolute, trusty, upstream, xenial): DNE 1048, ignored 169, needed 111, released 83, not-affected 33, needs-triage 5. https://ubuntu.com/security/CVE-2026-43061

Affected software / configurations for CVE-2026-43061

Vendor Product Version Raw CPE
linux linux_kernel >= 5.4.291, < 5.5 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 5.10.235, < 5.10.253 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 5.15.179, < 5.15.203 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 6.1.129, < 6.1.167 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 6.6.79, < 6.6.130 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 6.12.16, < 6.12.78 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 6.13.4, < 6.14 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 6.14.1, < 6.18.20 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 6.19, < 6.19.10 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel 6.14 cpe:2.3:o:linux:linux_kernel:6.14:-:*:*:*:*:*:*
linux linux_kernel 6.14 cpe:2.3:o:linux:linux_kernel:6.14:rc3:*:*:*:*:*:*
linux linux_kernel 6.14 cpe:2.3:o:linux:linux_kernel:6.14:rc4:*:*:*:*:*:*
linux linux_kernel 6.14 cpe:2.3:o:linux:linux_kernel:6.14:rc5:*:*:*:*:*:*
linux linux_kernel 6.14 cpe:2.3:o:linux:linux_kernel:6.14:rc6:*:*:*:*:*:*
linux linux_kernel 6.14 cpe:2.3:o:linux:linux_kernel:6.14:rc7:*:*:*:*:*:*
linux linux_kernel 7.0 cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:*
linux linux_kernel 7.0 cpe:2.3:o:linux:linux_kernel:7.0:rc2:*:*:*:*:*:*
linux linux_kernel 7.0 cpe:2.3:o:linux:linux_kernel:7.0:rc3:*:*:*:*:*:*
linux linux_kernel 7.0 cpe:2.3:o:linux:linux_kernel:7.0:rc4:*:*:*:*:*:*
linux linux_kernel 7.0 cpe:2.3:o:linux:linux_kernel:7.0:rc5:*:*:*:*:*:*
linux linux_kernel 7.0 cpe:2.3:o:linux:linux_kernel:7.0:rc6:*:*:*:*:*:*
linux linux_kernel 7.0 cpe:2.3:o:linux:linux_kernel:7.0:rc7:*:*:*:*:*:*

References for CVE-2026-43061

cvelogic Threat Intelligence