NVD / CVE Program· CNA Linux

CVE-2026-45984: gfs2: Fix use-after-free in iomap inline data write path

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: 0.18% (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 1403989d1b502f4a2c0d0b42ccf1c25748442eff, 1cae1bafdf9caa9b462b19af06b1a06902e4e142, 6d76febba07c40bcf358f63216d36ea68cf1c215.
Mentioned 1 time in Turkish national cyber security advisories (siberguvenlik.gov.tr).

Low priority for now. Upgrade to Linux Linux 1403989d1b502f4a2c0d0b42ccf1c25748442eff, 1cae1bafdf9caa9b462b19af06b1a06902e4e142, 6d76febba07c40bcf358f63216d36ea68cf1c215 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: gfs2: Fix use-after-free in iomap inline data write path The inline data buffer head (dibh) is being released prematurely in gfs2_iomap_begin() via release_metapath() while iomap->inline_data still points to dibh->b_data. This causes a use-after-free when iomap_write_end_inline() later attempts to write to the inline data area. The bug sequence: 1. gfs2_iomap_begin() calls gfs2_meta_inode_buffer() to read inode metadata into dibh 2. Sets iomap->inline_data = dibh->b_data + sizeof(struct gfs2_dinode) 3. Calls release_metapath() which calls brelse(dibh), dropping refcount to 0 4. kswapd reclaims the page (~39ms later in the syzbot report) 5. iomap_write_end_inline() tries to memcpy() to iomap->inline_data 6. KASAN detects use-after-free write to freed memory Fix by storing dibh in iomap->private and incrementing its refcount with get_bh() in gfs2_iomap_begin(). The buffer is then properly released in gfs2_iomap_end() after the inline write completes, ensuring the page stays alive for the entire iomap operation. Note: A C reproducer is not available for this issue. The fix is based on analysis of the KASAN report and code review showing the buffer head is freed before use. [agruenba: Take buffer head reference in gfs2_iomap_begin() to avoid leaks in gfs2_iomap_get() and gfs2_iomap_alloc().]

HighCVSS 7.8 · v3.1—No exploit Fix available

Memory safety

Published: May 27, 2026
Updated: Oct 19, 2026
EPSS: 0.1% · 8th percentile
CWE: CWE-416

Report tools

JSON

Action score

Monitor

Low priority for now.

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

CISA SSVC decision

Exploitation: none
Automatable: no
Technical impact: total

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD: —
CNA · Linux: 7.8; NVD has not scored this yet; the score shown is the CNA’s.

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

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

If any of these changes, we'll tell you in the daily email digest.

Running WordPress? Scan your site free with WP Lens

Is your version affected? Check it

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.

We use this product, ask for help

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 kernel5.2 and later · before 5.10.252
linux linux kernel5.11 and later · before 5.15.202
linux linux kernel5.16 and later · before 6.1.165
linux linux kernel6.2 and later · before 6.6.128
linux linux kernel6.7 and later · before 6.12.75
linux linux kernel6.13 and later · before 6.18.14
linux linux kernel6.19 and later · before 6.19.4

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
- 5.2affected
- d0a22a4b03b8475b7aa3fa41243c26c291407844 and later · before 1403989d1b502f4a2c0d0b42ccf1c25748442effaffected · git
- d0a22a4b03b8475b7aa3fa41243c26c291407844 and later · before 1cae1bafdf9caa9b462b19af06b1a06902e4e142affected · git
- d0a22a4b03b8475b7aa3fa41243c26c291407844 and later · before 764c3c84b5683e608f43735c803a5f415046686caffected · git
- d0a22a4b03b8475b7aa3fa41243c26c291407844 and later · before d87268326b277af3665237ac76a73dd9fa8e21b4affected · git
- d0a22a4b03b8475b7aa3fa41243c26c291407844 and later · before 87d4954b5c59735a99ea98cb208d47130f6dce7daffected · git
- d0a22a4b03b8475b7aa3fa41243c26c291407844 and later · before 6d76febba07c40bcf358f63216d36ea68cf1c215affected · git
- d0a22a4b03b8475b7aa3fa41243c26c291407844 and later · before 815ddd27c0c7171a99fe802fdb19098ddef8b19daffected · git
- d0a22a4b03b8475b7aa3fa41243c26c291407844 and later · before faddeb848305e79db89ee0479bb0e33380656321affected · git
- before 5.2not affected · semver

Package-level exposure

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

Ecosystem	Package	Affected range	Fix
AlmaLinux:8	bpftool	before 4.18.0-553.139.1.el8_10	4.18.0-553.139.1.el8_10
AlmaLinux:8	kernel	before 4.18.0-553.139.1.el8_10	4.18.0-553.139.1.el8_10
AlmaLinux:8	kernel-abi-stablelists	before 4.18.0-553.139.1.el8_10	4.18.0-553.139.1.el8_10
AlmaLinux:8	kernel-core	before 4.18.0-553.139.1.el8_10	4.18.0-553.139.1.el8_10
AlmaLinux:8	kernel-cross-headers	before 4.18.0-553.139.1.el8_10	4.18.0-553.139.1.el8_10
AlmaLinux:8	kernel-debug	before 4.18.0-553.139.1.el8_10	4.18.0-553.139.1.el8_10
AlmaLinux:8	kernel-debug-core	before 4.18.0-553.139.1.el8_10	4.18.0-553.139.1.el8_10
AlmaLinux:8	kernel-debug-devel	before 4.18.0-553.139.1.el8_10	4.18.0-553.139.1.el8_10
AlmaLinux:8	kernel-debug-modules	before 4.18.0-553.139.1.el8_10	4.18.0-553.139.1.el8_10
AlmaLinux:8	kernel-debug-modules-extra	before 4.18.0-553.139.1.el8_10	4.18.0-553.139.1.el8_10
AlmaLinux:8	kernel-devel	before 4.18.0-553.139.1.el8_10	4.18.0-553.139.1.el8_10
AlmaLinux:8	kernel-doc	before 4.18.0-553.139.1.el8_10	4.18.0-553.139.1.el8_10
AlmaLinux:8	kernel-headers	before 4.18.0-553.139.1.el8_10	4.18.0-553.139.1.el8_10
AlmaLinux:8	kernel-modules	before 4.18.0-553.139.1.el8_10	4.18.0-553.139.1.el8_10
AlmaLinux:8	kernel-modules-extra	before 4.18.0-553.139.1.el8_10	4.18.0-553.139.1.el8_10
AlmaLinux:8	kernel-rt	before 4.18.0-553.139.1.rt7.480.el8_10	4.18.0-553.139.1.rt7.480.el8_10
AlmaLinux:8	kernel-rt-core	before 4.18.0-553.139.1.rt7.480.el8_10	4.18.0-553.139.1.rt7.480.el8_10
AlmaLinux:8	kernel-rt-debug	before 4.18.0-553.139.1.rt7.480.el8_10	4.18.0-553.139.1.rt7.480.el8_10
AlmaLinux:8	kernel-rt-debug-core	before 4.18.0-553.139.1.rt7.480.el8_10	4.18.0-553.139.1.rt7.480.el8_10
AlmaLinux:8	kernel-rt-debug-devel	before 4.18.0-553.139.1.rt7.480.el8_10	4.18.0-553.139.1.rt7.480.el8_10
AlmaLinux:8	kernel-rt-debug-modules	before 4.18.0-553.139.1.rt7.480.el8_10	4.18.0-553.139.1.rt7.480.el8_10
AlmaLinux:8	kernel-rt-debug-modules-extra	before 4.18.0-553.139.1.rt7.480.el8_10	4.18.0-553.139.1.rt7.480.el8_10
AlmaLinux:8	kernel-rt-devel	before 4.18.0-553.139.1.rt7.480.el8_10	4.18.0-553.139.1.rt7.480.el8_10
AlmaLinux:8	kernel-rt-modules	before 4.18.0-553.139.1.rt7.480.el8_10	4.18.0-553.139.1.rt7.480.el8_10

+96

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-2026-45972May 27, 2026 · smb: client: fix potential UAF and double free in smb2_open_file()
39Monitor
← EarlierCVE-2026-45973May 27, 2026 · RDMA/mlx5: Fix UMR hang in LAG error state unload
22Monitor
Later →CVE-2026-45985May 27, 2026 · ext4: don't set EXT4_GET_BLOCKS_CONVERT when splitting before submitting I/O
22Monitor

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	1403989d1b502f4a2c0d0b42ccf1c25748442eff	Vendor (CNA)
Linux Linux	1cae1bafdf9caa9b462b19af06b1a06902e4e142	Vendor (CNA)
Linux Linux	6d76febba07c40bcf358f63216d36ea68cf1c215	Vendor (CNA)
Linux Linux	764c3c84b5683e608f43735c803a5f415046686c	Vendor (CNA)
Linux Linux	815ddd27c0c7171a99fe802fdb19098ddef8b19d	Vendor (CNA)
Linux Linux	87d4954b5c59735a99ea98cb208d47130f6dce7d	Vendor (CNA)
Linux Linux	d87268326b277af3665237ac76a73dd9fa8e21b4	Vendor (CNA)
Linux Linux	faddeb848305e79db89ee0479bb0e33380656321	Vendor (CNA)
almalinux:kernel	5.14.0-687.17.1.el9_8 · AlmaLinux:9	Package registry (OSV)
almalinux:kernel-64k	5.14.0-687.17.1.el9_8 · AlmaLinux:9	Package registry (OSV)
almalinux:kernel-64k-core	5.14.0-687.17.1.el9_8 · AlmaLinux:9	Package registry (OSV)
almalinux:kernel-64k-debug	5.14.0-687.17.1.el9_8 · AlmaLinux:9	Package registry (OSV)
almalinux:kernel-64k-debug-core	5.14.0-687.17.1.el9_8 · AlmaLinux:9	Package registry (OSV)
almalinux:kernel-64k-debug-devel	5.14.0-687.17.1.el9_8 · AlmaLinux:9	Package registry (OSV)
almalinux:kernel-64k-debug-devel-matched	5.14.0-687.17.1.el9_8 · AlmaLinux:9	Package registry (OSV)
almalinux:kernel-64k-debug-modules	5.14.0-687.17.1.el9_8 · AlmaLinux:9	Package registry (OSV)
almalinux:kernel-64k-debug-modules-core	5.14.0-687.17.1.el9_8 · AlmaLinux:9	Package registry (OSV)
almalinux:kernel-64k-debug-modules-extra	5.14.0-687.17.1.el9_8 · AlmaLinux:9	Package registry (OSV)
almalinux:kernel-64k-devel	5.14.0-687.17.1.el9_8 · AlmaLinux:9	Package registry (OSV)
almalinux:kernel-64k-devel-matched	5.14.0-687.17.1.el9_8 · AlmaLinux:9	Package registry (OSV)
debian:linux	6.1.170-1 · Debian:12	Package registry (OSV)
red hat:kernel-64k-debug-debuginfo	0:5.14.0-687.17.1.el9_8 · Red Hat:enterprise_linux:9::appstream	Package registry (OSV)
red hat:kernel-64k-debug-devel	0:5.14.0-687.17.1.el9_8 · Red Hat:enterprise_linux:9::appstream	Package registry (OSV)
red hat:kernel-64k-debug-devel-matched	0:5.14.0-687.17.1.el9_8 · Red Hat:enterprise_linux:9::appstream	Package registry (OSV)
red hat:kernel-64k-debuginfo	0:5.14.0-687.17.1.el9_8 · Red Hat:enterprise_linux:9::appstream	Package registry (OSV)
red hat:kernel-64k-devel	0:5.14.0-687.17.1.el9_8 · Red Hat:enterprise_linux:9::appstream	Package registry (OSV)
red hat:kernel-64k-devel-matched	0:5.14.0-687.17.1.el9_8 · Red Hat:enterprise_linux:9::appstream	Package registry (OSV)
red hat:kernel-debug-debuginfo	0:5.14.0-687.17.1.el9_8 · Red Hat:enterprise_linux:9::appstream	Package registry (OSV)
red hat:kernel-debug-devel	0:5.14.0-687.17.1.el9_8 · Red Hat:enterprise_linux:9::appstream	Package registry (OSV)
red hat:kernel-debug-devel-matched	0:5.14.0-687.17.1.el9_8 · Red Hat:enterprise_linux:9::appstream	Package registry (OSV)

+16

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-26-0290 · Jun 2, 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-secondary

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

SSVC exploitation— → noneOct 16, 2026, 5:07 PM UTC
Fix✗ → ✓Sep 28, 2026, 10:11 PM UTC

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

References

git.kernel.org/stable/c/1403989d1b502f4a2c0d0b42ccf1c25748442eff

Show all references (19 more)

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

All records