Linux Kernel up to 6.6.139/6.12.85/6.18.26/7.0.3 ibmasm command_file_write out-of-bounds

CVSS Meta Temp Score
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CTI Interest Score
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5.2$0-$5k0.00

Summaryinfo

A vulnerability labeled as critical has been found in Linux Kernel up to 6.6.139/6.12.85/6.18.26/7.0.3. Affected by this issue is the function command_file_write of the component ibmasm. The manipulation results in out-of-bounds. This vulnerability is known as CVE-2026-45994. No exploit is available. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.6.139/6.12.85/6.18.26/7.0.3. It has been classified as problematic. Affected is the function command_file_write of the component ibmasm. The manipulation with an unknown input leads to a out-of-bounds vulnerability. CWE is classifying the issue as CWE-125. The product reads data past the end, or before the beginning, of the intended buffer. This is going to have an impact on confidentiality. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: ibmasm: fix OOB reads in command_file_write due to missing size checks The command_file_write() handler allocates a kernel buffer of exactly count bytes and copies user data into it, but does not validate the buffer against the dot command protocol before passing it to get_dot_command_size() and get_dot_command_timeout(). Since both the allocation size (count) and the header fields (command_size, data_size) are independently user-controlled, an attacker can cause get_dot_command_size() to return a value exceeding the allocation, triggering OOB reads in get_dot_command_timeout() and an out-of-bounds memcpy_toio() that leaks kernel heap memory to the service processor. Fix with two guards: reject writes smaller than sizeof(struct dot_command_header) before allocation, then after copying user data reject commands where the buffer is smaller than the total size declared by the header (sizeof(header) + command_size + data_size). This ensures all subsequent header and payload field accesses stay within the buffer.

The advisory is shared for download at git.kernel.org. This vulnerability is traded as CVE-2026-45994 since 05/13/2026. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $0-$5k (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, 6.12.86, 6.18.27, 7.0.4 or 7.1-rc1 eliminates this vulnerability. Applying the patch a672682d39dd34e2b5ba4feb436723bed65125ff/aefc1a97da17d8309974690c8a03e439a91ebb1c/ee5737891464030a189837467df3b81a273718ad/d0fb4d1dc43f8d5179917a2daaa82680993d4cdf/0eb09f737428e482a32a2e31e5e223f2b35a71d3 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

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Version

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.3
VulDB Meta Temp Score: 5.2

VulDB Base Score: 3.5
VulDB Temp Score: 3.4
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 7.1
NVD Vector: 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Out-of-bounds
CWE: CWE-125 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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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 6.6.140/6.12.86/6.18.27/7.0.4/7.1-rc1
Patch: a672682d39dd34e2b5ba4feb436723bed65125ff/aefc1a97da17d8309974690c8a03e439a91ebb1c/ee5737891464030a189837467df3b81a273718ad/d0fb4d1dc43f8d5179917a2daaa82680993d4cdf/0eb09f737428e482a32a2e31e5e223f2b35a71d3

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-2026-45994 (🔒)
GCVE (CVE): GCVE-0-2026-45994
GCVE (VulDB): GCVE-100-366180

Entryinfo

Created: 05/27/2026 17:06
Updated: 07/06/2026 08:47
Changes: 05/27/2026 17:06 (59), 06/16/2026 17:17 (11), 07/06/2026 08:47 (2)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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