CVE-2026-98748 json
serial: 8250_bcm7271: fix use-after-free in brcmuart_remove()
published 24d ago modified 12d ago also EUVD-2026-103833
- cvss
- —
- not scored
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.2%
- EPSS 0.2% chance of exploitation in 30 days, percentile 6%
- public exploits
- 0
- none known
Summary
In the Linux kernel, the following vulnerability has been resolved:
serial: 8250_bcm7271: fix use-after-free in brcmuart_remove()
brcmuart_handle_irq() starts priv->hrt to work around a receive-timeout quirk of the 8250 core when hardware flow control is enabled; the timer callback brcmuart_hrtimer_func() dereferences priv.
brcmuart_remove() cancels the hrtimer before it unregisters the port, so a receive-timeout interrupt that arrives in between re-arms the timer. After devm frees priv, the callback runs on freed memory.
Unregister the port before cancelling the hrtimer. serial8250_unregister_port() shuts the port down and frees its IRQ, so brcmuart_handle_irq() can no longer restart the timer, and the final hrtimer_cancel() drains any timer that was armed before or during the unregister.
This issue was found by an in-house static analysis tool.
Patch / fix
- Linux Linux 7.3
- linux Debian 13 6.12.113-1
- linux Debian 14 7.2.10-1
- linux-6.12 Debian 12 6.12.113-1~deb12u1
debian advisories DEBIAN-CVE-2026-98748
- linux Ubuntu 24.04 LTS 6.8.0-149.149
- linux Ubuntu 26.04 LTS 7.0.0-43.43
- linux-aws Ubuntu 24.04 LTS 6.8.0-1069.74
- linux-aws Ubuntu 26.04 LTS 7.0.0-1017.18
- linux-gcp Ubuntu 24.04 LTS 6.8.0-1073.81
- linux-gcp Ubuntu 26.04 LTS 7.0.0-1017.19
- linux-gke Ubuntu 24.04 LTS 6.8.0-1068.77
- linux-gke Ubuntu 26.04 LTS 7.0.0-1010.11
ubuntu advisories UBUNTU-CVE-2026-98748
Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0
- kernel-source Linux Micro 6.0 6.4.0-159998.55.1
- kernel-default Linux Micro 6.0 6.4.0-159998.55.1
- kernel-kvmsmall Linux Micro 6.0 6.4.0-159998.55.1
- kernel-default-base Linux Micro 6.0 6.4.0-159998.55.1.159998.21.42
- kernel-64kb SLE Module for Basesystem 15 SP7 6.4.0-150700.53.90.1
- kernel-syms SLE Module for Development Tools 15 SP7 6.4.0-150700.53.90.1
- kernel-azure SLE Module for Public Cloud 15 SP7 6.4.0-150700.53.90.1
- kernel-source SLE Module for Development Tools 15 SP7, SLE Module for Basesystem 15 SP7 6.4.0-150700.53.90.1
suse advisories SUSE-SU-2026:24550-1SUSE-SU-2026:5091-1
- kernel Azure Linux 3.0 6.6.161.1-1
azure linux advisories AZL-109419
Azure Linux vulnerability data, Copyright (c) Microsoft Corporation, from https://github.com/microsoft/AzureLinuxVulnerabilityData via OSV, under the MIT licence; changed: normalised to fixed package versions per release. MIT
- git.kernel.org/stable/c/134d239558f2ac2602fad2392ec3e6d8d76af7d8 commit
- git.kernel.org/stable/c/dad9fb86829ee96bbc6315d7209ceb24820ef889 commit
- git.kernel.org/stable/c/dd81650bec58ac70e5dfde2ec390acc1f0d1ed76 commit
- git.kernel.org/stable/c/f5ce06e648d775cc1ccf66f4f594bb8b559a7d8e commit
- git.kernel.org/stable/c/e32440fa536af96bdbc61d933a7c3a920b965edc commit
- git.kernel.org/stable/c/0794ba5332754866b2f1c0cca668775be3ffcf0a commit
- git.kernel.org/stable/c/189b9dc8c96ec9486482f27c1372b04a7152175e commit
Is CVE-2026-98748 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerVendor advisories
What the vendors themselves say about their products: affected, fixed or not affected, and what to do.
red hat product security vex CVE-2026-98748 updated cvss 4.1
kernel: kernel: Denial of Service via use-after-free in Broadcom serial driver
-
Red Hat Enterprise Linux 10 kernelaffected: workaround, no fix available “Fix deferred”
Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf
Exploit prediction
0.17% chance of exploitation in the next 30 days, higher than 6% of all scored CVEs (FIRST EPSS, 2026-11-11).
Affected products
- Linux Linux
Classification
- Technology feeds
References
- git.kernel.org /stable/c/134d239558f2ac2602fad2392ec3e6d8d76af7d8
- git.kernel.org /stable/c/dad9fb86829ee96bbc6315d7209ceb24820ef889
- git.kernel.org /stable/c/dd81650bec58ac70e5dfde2ec390acc1f0d1ed76
- git.kernel.org /stable/c/f5ce06e648d775cc1ccf66f4f594bb8b559a7d8e
- git.kernel.org /stable/c/e32440fa536af96bdbc61d933a7c3a920b965edc
- git.kernel.org /stable/c/0794ba5332754866b2f1c0cca668775be3ffcf0a
- git.kernel.org /stable/c/189b9dc8c96ec9486482f27c1372b04a7152175e
Sources
- CVE List CVE-2026-98748
- NVD CVE-2026-98748
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.