Linux Kernel up to 7.2-rc4 btrfs __add_reloc_root allocation of resources

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.0$0-$5k1.58

Summaryinfo

A vulnerability categorized as critical has been discovered in Linux Kernel up to 6.6.147/6.12.100/6.18.41/7.1.5/7.2-rc4. The affected element is the function __add_reloc_root of the component btrfs. Executing a manipulation can lead to allocation of resources. This vulnerability is registered as CVE-2026-68450. It is possible to launch the attack remotely. No exploit is available.

Detailsinfo

A vulnerability classified as critical was found in Linux Kernel up to 6.6.147/6.12.100/6.18.41/7.1.5/7.2-rc4. This vulnerability affects the function __add_reloc_root of the component btrfs. The manipulation with an unknown input leads to a allocation of resources vulnerability. The CWE definition for the vulnerability is CWE-770. The product allocates a reusable resource or group of resources on behalf of an actor without imposing any restrictions on the size or number of resources that can be allocated, in violation of the intended security policy for that actor. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: btrfs: free mapping node on duplicate reloc root insert __add_reloc_root() allocates a mapping_node before inserting it into rc->reloc_root_tree. If rb_simple_insert() finds an existing entry, it returns the existing rb_node and leaves the newly allocated node unlinked. The error path then returns -EEXIST without freeing the new node. Since the node was never inserted into reloc_root_tree, the later cleanup in put_reloc_control() cannot find it either. Free the newly allocated node before returning -EEXIST. The callers currently assert that -EEXIST should not happen, so this is a defensive cleanup for an unexpected duplicate insert path. If the path is ever reached, the local allocation should still be released.

The advisory is shared for download at git.kernel.org. This vulnerability was named CVE-2026-68450 since 07/30/2026. The exploitation appears to be easy. The attack can be initiated remotely. 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 08/12/2026). The MITRE ATT&CK project declares the attack technique as T1499.

Upgrading to version 6.6.148, 6.12.101, 6.18.42, 7.1.6 or 7.2-rc5 eliminates this vulnerability. Applying the patch 92bedc0455552b42ada1a1f42b0e3a8593cdfccc/14a8be9428435ee17f17fae7991215c246b7fd43/797dc567146c7e3c4f8d9680e4fbc76e0a6d9151/ae0629ff9ccb836416ada129f4edc7efea6eaaad/6a8269b6459ed870a8156c106a0f597383907872 is able to eliminate this problem.

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Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.3
VulDB Meta Temp Score: 6.0

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

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

Exploitinginfo

Class: Allocation of resources
CWE: CWE-770 / CWE-400 / CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 6.6.148/6.12.101/6.18.42/7.1.6/7.2-rc5
Patch: 92bedc0455552b42ada1a1f42b0e3a8593cdfccc/14a8be9428435ee17f17fae7991215c246b7fd43/797dc567146c7e3c4f8d9680e4fbc76e0a6d9151/ae0629ff9ccb836416ada129f4edc7efea6eaaad/6a8269b6459ed870a8156c106a0f597383907872

Timelineinfo

07/30/2026 CVE reserved
08/12/2026 +13 days Advisory disclosed
08/12/2026 +0 days VulDB entry created
08/12/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-68450 (🔒)
GCVE (CVE): GCVE-0-2026-68450
GCVE (VulDB): GCVE-100-388900

Entryinfo

Created: 08/12/2026 03:27
Changes: 08/12/2026 03:27 (59)
Complete: 🔍
Cache ID: 216::103

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