NVD / CVE Program· CNA Linux

CVE-2024-49889: ext4: avoid use-after-free in ext4_ext_show_leaf()

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: 0.25% (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 2eba3b0cc5b8de624918d21f32b5b8db59a90b39, 34b2096380ba475771971a778a478661a791aa15, 4999fed877bb64e3e7f9ab9996de2ca983c41928; Azure Linux 3.0 ARM 6.6.57.1-2; Azure Linux 3.0 x64 6.6.57.1-2.

Low priority for now. Upgrade to Linux Linux 2eba3b0cc5b8de624918d21f32b5b8db59a90b39, 34b2096380ba475771971a778a478661a791aa15, 4999fed877bb64e3e7f9ab9996de2ca983c41928; Azure Linux 3.0 ARM 6.6.57.1-2; Azure Linux 3.0 x64 6.6.57.1-2 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: ext4: avoid use-after-free in ext4_ext_show_leaf() In ext4_find_extent(), path may be freed by error or be reallocated, so using a previously saved *ppath may have been freed and thus may trigger use-after-free, as follows: ext4_split_extent path = *ppath; ext4_split_extent_at(ppath) path = ext4_find_extent(ppath) ext4_split_extent_at(ppath) // ext4_find_extent fails to free path // but zeroout succeeds ext4_ext_show_leaf(inode, path) eh = path[depth].p_hdr // path use-after-free !!! Similar to ext4_split_extent_at(), we use *ppath directly as an input to ext4_ext_show_leaf(). Fix a spelling error by the way. Same problem in ext4_ext_handle_unwritten_extents(). Since 'path' is only used in ext4_ext_show_leaf(), remove 'path' and use *ppath directly. This issue is triggered only when EXT_DEBUG is defined and therefore does not affect functionality.

HighCVSS 7.8 · v3.1—No exploit Fix available

Memory safety

BDU:2024-09791

Published: Oct 21, 2024
Updated: Oct 15, 2026
EPSS: 0.2% · 17th 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 · 0.2%

CISA SSVC decision

Exploitation: none
Automatable: no
Technical impact: partial

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD: 7.8
CNA · Linux: 7.8; agree

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

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Noroxi analysis

What does it mean in your environment?

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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 kernelbefore 5.10.227
linux linux kernel5.11 and later · before 5.15.168
linux linux kernel5.16 and later · before 6.1.113
linux linux kernel6.2 and later · before 6.6.55
linux linux kernel6.7 and later · before 6.10.14
linux linux kernel6.11 and later · before 6.11.3

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
- 3.18affected
- dfe5080939ea4686b3414b5d970a9b26733c57a4 and later · before b0cb4561fc4284d04e69c8a66c8504928ab2484eaffected · git
- dfe5080939ea4686b3414b5d970a9b26733c57a4 and later · before 4999fed877bb64e3e7f9ab9996de2ca983c41928affected · git
- dfe5080939ea4686b3414b5d970a9b26733c57a4 and later · before 2eba3b0cc5b8de624918d21f32b5b8db59a90b39affected · git
- dfe5080939ea4686b3414b5d970a9b26733c57a4 and later · before 34b2096380ba475771971a778a478661a791aa15affected · git
- dfe5080939ea4686b3414b5d970a9b26733c57a4 and later · before 8b114f2cc7dd5d36729d040b68432fbd0f0a8868affected · git
- dfe5080939ea4686b3414b5d970a9b26733c57a4 and later · before d483c7cc1796bd6a80e7b3a8fd494996260f6b67affected · git
- dfe5080939ea4686b3414b5d970a9b26733c57a4 and later · before 4e2524ba2ca5f54bdbb9e5153bea00421ef653f5affected · git
- before 3.18not affected · semver
- 5.10.227 and later · up to and including 5.10.*not 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 6.1.115-1	6.1.115-1
Debian:13	linux	before 6.11.4-1	6.11.4-1

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-2024-49885Oct 21, 2024 · mm, slub: avoid zeroing kmalloc redzone
22Monitor
← EarlierCVE-2024-49888Oct 21, 2024 · bpf: Fix a sdiv overflow issue
22Monitor
Later →CVE-2024-49890Oct 21, 2024 · drm/amd/pm: ensure the fw_info is not null before using it
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	2eba3b0cc5b8de624918d21f32b5b8db59a90b39	Vendor (CNA)
Linux Linux	34b2096380ba475771971a778a478661a791aa15	Vendor (CNA)
Linux Linux	4999fed877bb64e3e7f9ab9996de2ca983c41928	Vendor (CNA)
Linux Linux	4e2524ba2ca5f54bdbb9e5153bea00421ef653f5	Vendor (CNA)
Linux Linux	8b114f2cc7dd5d36729d040b68432fbd0f0a8868	Vendor (CNA)
Linux Linux	b0cb4561fc4284d04e69c8a66c8504928ab2484e	Vendor (CNA)
Linux Linux	d483c7cc1796bd6a80e7b3a8fd494996260f6b67	Vendor (CNA)
Azure Linux 3.0 ARM	6.6.57.1-2 · kernel	Microsoft (MSRC)
Azure Linux 3.0 x64	6.6.57.1-2 · kernel	Microsoft (MSRC)
debian:linux	6.1.115-1 · 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).

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/2eba3b0cc5b8de624918d21f32b5b8db59a90b39

Show all references (10 more)

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

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