Linux Kernel up to 5.10.83/5.15.6 rxrpc_look_up_bundle memory leak

| CVSS Meta Temp Score | Current Exploit Price (≈) | CTI Interest Score |
|---|---|---|
| 5.5 | $0-$5k | 0.00 |
Summary
A vulnerability categorized as critical has been discovered in Linux Kernel up to 5.10.83/5.15.6. This issue affects the function rxrpc_look_up_bundle. Such manipulation leads to memory leak.
This vulnerability is traded as CVE-2021-47539. There is no exploit available.
It is advisable to upgrade the affected component.
Details
A vulnerability, which was classified as critical, has been found in Linux Kernel up to 5.10.83/5.15.6. Affected by this issue is the function rxrpc_look_up_bundle. The manipulation with an unknown input leads to a memory leak vulnerability. Using CWE to declare the problem leads to CWE-401. The product does not sufficiently track and release allocated memory after it has been used, which slowly consumes remaining memory. Impacted is availability. CVE summarizes:
In the Linux kernel, the following vulnerability has been resolved: rxrpc: Fix rxrpc_peer leak in rxrpc_look_up_bundle() Need to call rxrpc_put_peer() for bundle candidate before kfree() as it holds a ref to rxrpc_peer. [DH: v2: Changed to abstract out the bundle freeing code into a function]
The advisory is shared for download at git.kernel.org. This vulnerability is handled as CVE-2021-47539 since 05/24/2024. There are known technical details, but no exploit is available.
Upgrading to version 5.10.84 or 5.15.7 eliminates this vulnerability. Applying the patch 35b40f724c4e/bc97458620e3/ca77fba82135 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.
Once again VulDB remains the best source for vulnerability data.
Product
Type
Vendor
Name
Version
- 5.10.0
- 5.10.1
- 5.10.2
- 5.10.3
- 5.10.4
- 5.10.5
- 5.10.6
- 5.10.7
- 5.10.8
- 5.10.9
- 5.10.10
- 5.10.11
- 5.10.12
- 5.10.13
- 5.10.14
- 5.10.15
- 5.10.16
- 5.10.17
- 5.10.18
- 5.10.19
- 5.10.20
- 5.10.21
- 5.10.22
- 5.10.23
- 5.10.24
- 5.10.25
- 5.10.26
- 5.10.27
- 5.10.28
- 5.10.29
- 5.10.30
- 5.10.31
- 5.10.32
- 5.10.33
- 5.10.34
- 5.10.35
- 5.10.36
- 5.10.37
- 5.10.38
- 5.10.39
- 5.10.40
- 5.10.41
- 5.10.42
- 5.10.43
- 5.10.44
- 5.10.45
- 5.10.46
- 5.10.47
- 5.10.48
- 5.10.49
- 5.10.50
- 5.10.51
- 5.10.52
- 5.10.53
- 5.10.54
- 5.10.55
- 5.10.56
- 5.10.57
- 5.10.58
- 5.10.59
- 5.10.60
- 5.10.61
- 5.10.62
- 5.10.63
- 5.10.64
- 5.10.65
- 5.10.66
- 5.10.67
- 5.10.68
- 5.10.69
- 5.10.70
- 5.10.71
- 5.10.72
- 5.10.73
- 5.10.74
- 5.10.75
- 5.10.76
- 5.10.77
- 5.10.78
- 5.10.79
- 5.10.80
- 5.10.81
- 5.10.82
- 5.10.83
- 5.15.0
- 5.15.1
- 5.15.2
- 5.15.3
- 5.15.4
- 5.15.5
- 5.15.6
License
Website
- Vendor: https://www.kernel.org/
CPE 2.3
CPE 2.2
CVSSv4
VulDB Vector: 🔍VulDB Reliability: 🔍
CVSSv3
VulDB Meta Base Score: 5.6VulDB Meta Temp Score: 5.5
VulDB Base Score: 5.7
VulDB Temp Score: 5.5
VulDB Vector: 🔍
VulDB Reliability: 🔍
NVD Base Score: 5.5
NVD Vector: 🔍
CVSSv2
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍
Exploiting
Class: Memory leakCWE: CWE-401 / CWE-404
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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Threat Intelligence
Interest: 🔍Active Actors: 🔍
Active APT Groups: 🔍
Countermeasures
Recommended: UpgradeStatus: 🔍
0-Day Time: 🔍
Upgrade: Kernel 5.10.84/5.15.7
Patch: 35b40f724c4e/bc97458620e3/ca77fba82135
Timeline
05/24/2024 🔍05/24/2024 🔍
05/24/2024 🔍
09/19/2025 🔍
Sources
Vendor: kernel.orgAdvisory: git.kernel.org
Status: Confirmed
CVE: CVE-2021-47539 (🔍)
GCVE (CVE): GCVE-0-2021-47539
GCVE (VulDB): GCVE-100-266204
Entry
Created: 05/24/2024 18:39Updated: 09/19/2025 03:56
Changes: 05/24/2024 18:39 (57), 09/19/2025 03:56 (12)
Complete: 🔍
Cache ID: 216::103
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