NVD / CVE Program· CNA Linux

CVE-2026-43458: serial: caif: hold tty->link reference in ldisc_open and ser_release

Noroxi assessment

Priority: Monitor (action score 31/100)

The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
Probability of exploitation in the next 30 days: 0.11% (FIRST EPSS).
Someone with local access to the system can trigger it. A low-privileged account is enough. No user action is required. No special conditions are required; it is repeatable.
Fixed version: Linux Linux 23a3ac2e2262a291498567418227b99e1f3606b1, 27e43356d0defb9fc7fa25265219a3ffeb7b3e98, 288598d80a068a0e9281de35bcb4ce495f189e2a.
Mentioned 1 time in Turkish national cyber security advisories (siberguvenlik.gov.tr).

Low priority for now. Upgrade to Linux Linux 23a3ac2e2262a291498567418227b99e1f3606b1, 27e43356d0defb9fc7fa25265219a3ffeb7b3e98, 288598d80a068a0e9281de35bcb4ce495f189e2a or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

In the Linux kernel, the following vulnerability has been resolved: serial: caif: hold tty->link reference in ldisc_open and ser_release A reproducer triggers a KASAN slab-use-after-free in pty_write_room() when caif_serial's TX path calls tty_write_room(). The faulting access is on tty->link->port. Hold an extra kref on tty->link for the lifetime of the caif_serial line discipline: get it in ldisc_open() and drop it in ser_release(), and also drop it on the ldisc_open() error path. With this change applied, the reproducer no longer triggers the UAF in my testing.

HighCVSS 7.8 · v3.1—No exploit Fix available

Memory safety

Published: May 8, 2026
Updated: Jun 17, 2026
EPSS: 0.1% · 1th percentile
CWE: CWE-416

Report tools

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Action score

Monitor

Low priority for now.

CVSS: 31 / 40 · 7.8 / 10
CISA KEV: 0 / 30 · Not listed
EPSS: 0 / 30 · 0.1%

Get told when this record changes

Not in KEV: no record of exploitation in the wild
No public exploit code on record
A fix has been released

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

Vendor	Product	CPE
linux	linux kernel	cpe:2.3:o:linux:linux_kernel

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

linux linux kernel2.6.35 and later · before 5.10.253
linux linux kernel5.11 and later · before 5.15.203
linux linux kernel5.16 and later · before 6.1.167
linux linux kernel6.2 and later · before 6.6.130
linux linux kernel6.7 and later · before 6.12.78
linux linux kernel6.13 and later · before 6.18.19
linux linux kernel6.19 and later · before 6.19.9
linux linux kernel7.0

Versions reported by the vendor

Affected version ranges reported by the assigning authority (Linux). Independent of NVD's CPE analysis and usually ahead of it.

Linux Linux
- 2.6.35affected
- e31d5a05948e4478ba8396063d1e1f39880928e2 and later · before 23a3ac2e2262a291498567418227b99e1f3606b1affected · git
- e31d5a05948e4478ba8396063d1e1f39880928e2 and later · before 52135420e9f75853ea0c6cea7b736e3e98495f7daffected · git
- e31d5a05948e4478ba8396063d1e1f39880928e2 and later · before ca2ceba983bb23ea0202c2882d963253416654a3affected · git
- e31d5a05948e4478ba8396063d1e1f39880928e2 and later · before 8460187b4852fd00bd1c76394358053f3fa4d089affected · git
- e31d5a05948e4478ba8396063d1e1f39880928e2 and later · before 27e43356d0defb9fc7fa25265219a3ffeb7b3e98affected · git
- e31d5a05948e4478ba8396063d1e1f39880928e2 and later · before 35b58d3bc716ebb9ebd10fe1cac8c1177242511caffected · git
- e31d5a05948e4478ba8396063d1e1f39880928e2 and later · before 97a0bb491cae39478c6225381f14e9ac67b7bba7affected · git
- e31d5a05948e4478ba8396063d1e1f39880928e2 and later · before 288598d80a068a0e9281de35bcb4ce495f189e2aaffected · git
- before 2.6.35not affected · semver

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

Ecosystem	Package	Affected range	Fix
Debian:12	linux	before 6.1.170-1	6.1.170-1
Debian:13	linux	before 6.12.85-1	6.12.85-1
Debian:14	linux	before 6.19.10-1	6.19.10-1

Same product

linux: all records

Other highest-scoring records for the same primary product.

CVE-2026-31431crypto: algif_aead - Revert to operating out-of-placeKEV
90Now
CVE-2022-0847A flaw was found in the way the "flags" member of the new pipe buffer structure was lacking proper initialization in copy_page_to_iter_pipe KEV
89Now
CVE-2021-22555Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACEKEV
85Now

Published before and after this one in the same product

← EarlierCVE-2026-43455May 8, 2026 · mctp: route: hold key->lock in mctp_flow_prepare_output()
22Monitor
← EarlierCVE-2026-43457May 8, 2026 · mctp: i2c: fix skb memory leak in receive path
22Monitor
Later →CVE-2026-43460May 8, 2026 · spi: rockchip-sfc: Fix double-free in remove() callback
31Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / package	Fixed version	Source
Linux Linux	23a3ac2e2262a291498567418227b99e1f3606b1	Vendor (CNA)
Linux Linux	27e43356d0defb9fc7fa25265219a3ffeb7b3e98	Vendor (CNA)
Linux Linux	288598d80a068a0e9281de35bcb4ce495f189e2a	Vendor (CNA)
Linux Linux	35b58d3bc716ebb9ebd10fe1cac8c1177242511c	Vendor (CNA)
Linux Linux	52135420e9f75853ea0c6cea7b736e3e98495f7d	Vendor (CNA)
Linux Linux	8460187b4852fd00bd1c76394358053f3fa4d089	Vendor (CNA)
Linux Linux	97a0bb491cae39478c6225381f14e9ac67b7bba7	Vendor (CNA)
Linux Linux	ca2ceba983bb23ea0202c2882d963253416654a3	Vendor (CNA)
debian:linux	6.1.170-1 · Debian:12	Package registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

No history yet (it accumulates with the daily EPSS job).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

No nightly-computed relations.

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

National notice (Türkiye Cybersecurity Directorate / USOM)

Official security notices citing this record; remediation advice is on the agency's page.

TR-26-0213 · May 12, 2026(Linux Kernel Güvenlik Bildirimi)

All national notices →

Technical details

Attack conditions

Someone with local access to the system can trigger it.
A low-privileged account is enough.
No user action is required.
No special conditions are required; it is repeatable.

If successful

Confidentiality: high · data can be read
Integrity: high · data or configuration can be modified
Availability: high · the service can be disrupted

Attack vector: Local
Attack complexity: Low
Privileges required: Low
User interaction: None
Scope: Unchanged
Confidentiality impact: High
Integrity impact: High
Availability impact: High

Weakness class (CWE)

CWE-416 · Use After Free

CVSS vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

nvd-primary

Root cause

After a memory region is freed, another reference pointing to it is still used. By then, the same region may have been allocated for different data.

The bug in code

The whole CWE-416 class

A representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.

Vulnerable

1free(dev->buf);
2/* ... another thread is still running ... */
3process(dev->buf);

Fixed

1lock(&dev->lock);
2free(dev->buf);
3dev->buf = NULL;
4unlock(&dev->lock);

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

MITRE has no CAPEC/ATT&CK mapping for this CWE.

Change log

Fix✗ → ✓Sep 28, 2026, 10:11 PM UTC

For records you follow, these changes also arrive as notifications. →

References

git.kernel.org/stable/c/23a3ac2e2262a291498567418227b99e1f3606b1

Show all references (7 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records