Linux Kernel up to 6.6.139/6.12.87/6.18.29/7.0.3 z_erofs_lz4_handle_overlap integer overflow

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7.4	$5k-$25k	0.00

Summaryinfo

A vulnerability categorized as critical has been discovered in Linux Kernel up to 6.6.139/6.12.87/6.18.29/7.0.3. This impacts the function z_erofs_lz4_handle_overlap. The manipulation results in integer overflow. This vulnerability is identified as CVE-2026-45999. There is not any exploit available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, was found in Linux Kernel up to 6.6.139/6.12.87/6.18.29/7.0.3. Affected is the function z_erofs_lz4_handle_overlap. The manipulation with an unknown input leads to a integer overflow vulnerability. CWE is classifying the issue as CWE-190. The product performs a calculation that can produce an integer overflow or wraparound, when the logic assumes that the resulting value will always be larger than the original value. This can introduce other weaknesses when the calculation is used for resource management or execution control. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: erofs: fix unsigned underflow in z_erofs_lz4_handle_overlap() Some crafted images can have illegal (!partial_decoding && m_llen < m_plen) extents, and the LZ4 inplace decompression path can be wrongly hit, but it cannot handle (outpages < inpages) properly: "outpages - inpages" wraps to a large value and the subsequent rq->out[] access reads past the decompressed_pages array. However, such crafted cases can correctly result in a corruption report in the normal LZ4 non-inplace path. Let's add an additional check to fix this for backporting. Reproducible image (base64-encoded gzipped blob): H4sIAJGR12kCA+3SPUoDQRgG4MkmkkZk8QRbRFIIi9hbpEjrHQI5ghfwCN5BLCzTGtLbBI+g dilSJo1CnIm7GEXFxhT6PDDwfrs73/ywIQD/1ePD4r7Ou6ETsrq4mu7XcWfj++Pb58nJU/9i PNtbjhan04/9GtX4qVYc814WDqt6FaX5s+ZwXXeq52lndT6IuVvlblytLMvh4Gzwaf90nsvz 2DF/21+20T/ldgp5s1jXRaN4t/8izsy/OUB6e/Qa79r+JwAAAAAAAL52vQVuGQAAAP6+my1w ywAAAAAAAADwu14ATsEYtgBQAAA= $ mount -t erofs -o cache_strategy=disabled foo.erofs /mnt $ dd if=/mnt/data of=/dev/null bs=4096 count=1

The advisory is shared for download at git.kernel.org. This vulnerability is traded as CVE-2026-45999 since 05/13/2026. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $5k-$25k (estimation calculated on 07/06/2026).

The vulnerability scanner Nessus provides a plugin with the ID 325059 (Debian dla-4665 : affs-modules-6.1.0-48-4kc-malta-di - security update), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.6.140, 6.12.88, 6.18.30, 7.0.4 or 7.1-rc1 eliminates this vulnerability. Applying the patch 43a878639b90e9721ffa5eb616a7e6d8454adef3/f1374fa6e57fd836623668d782ded9244cfd2938/c9ce18e6bb2c467ec85756dc7989b547b7584fee/bbbbb3f0d7864238a8da2a94cd6ec013fee06a2e/21e161de2dc660b1bb70ef5b156ab8e6e1cca3ab is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the vulnerability database at Tenable (325059). Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 6.6.139
• 6.12.0
• 6.12.1
• 6.12.2
• 6.12.3
• 6.12.4
• 6.12.5
• 6.12.6
• 6.12.7
• 6.12.8
• 6.12.9
• 6.12.10
• 6.12.11
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• 6.12.27
• 6.12.28
• 6.12.29
• 6.12.30
• 6.12.31
• 6.12.32
• 6.12.33
• 6.12.34
• 6.12.35
• 6.12.36
• 6.12.37
• 6.12.38
• 6.12.39
• 6.12.40
• 6.12.41
• 6.12.42
• 6.12.43
• 6.12.44
• 6.12.45
• 6.12.46
• 6.12.47
• 6.12.48
• 6.12.49
• 6.12.50
• 6.12.51
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• 6.12.55
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• 6.12.57
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• 6.12.71
• 6.12.72
• 6.12.73
• 6.12.74
• 6.12.75
• 6.12.76
• 6.12.77
• 6.12.78
• 6.12.79
• 6.12.80
• 6.12.81
• 6.12.82
• 6.12.83
• 6.12.84
• 6.12.85
• 6.12.86
• 6.12.87
• 6.18.0
• 6.18.1
• 6.18.2
• 6.18.3
• 6.18.4
• 6.18.5
• 6.18.6
• 6.18.7
• 6.18.8
• 6.18.9
• 6.18.10
• 6.18.11
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• 6.18.13
• 6.18.14
• 6.18.15
• 6.18.16
• 6.18.17
• 6.18.18
• 6.18.19
• 6.18.20
• 6.18.21
• 6.18.22
• 6.18.23
• 6.18.24
• 6.18.25
• 6.18.26
• 6.18.27
• 6.18.28
• 6.18.29
• 7.0.0
• 7.0.1
• 7.0.2
• 7.0.3

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.6
VulDB Meta Temp Score: 7.4

VulDB Base Score: 8.0
VulDB Temp Score: 7.6
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 7.1
CNA Vector (Linux): 🔒

CVSSv2info

AV	AC	Au	C	I	A
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳
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Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Integer overflow
CWE: CWE-190 / CWE-189
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Nessus ID: 325059
Nessus Name: Debian dla-4665 : affs-modules-6.1.0-48-4kc-malta-di - security update

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 6.6.140/6.12.88/6.18.30/7.0.4/7.1-rc1
Patch: 43a878639b90e9721ffa5eb616a7e6d8454adef3/f1374fa6e57fd836623668d782ded9244cfd2938/c9ce18e6bb2c467ec85756dc7989b547b7584fee/bbbbb3f0d7864238a8da2a94cd6ec013fee06a2e/21e161de2dc660b1bb70ef5b156ab8e6e1cca3ab

Timelineinfo

05/13/2026 CVE reserved
05/27/2026 +14 days Advisory disclosed
05/27/2026 +0 days VulDB entry created
07/06/2026 +40 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-45999 (🔒)
GCVE (CVE): GCVE-0-2026-45999
GCVE (VulDB): GCVE-100-366276

Entryinfo

Created: 05/27/2026 17:26
Updated: 07/06/2026 08:47
Changes: 05/27/2026 17:26 (58), 06/16/2026 18:07 (11), 07/06/2026 08:47 (2)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

Discussion

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