Linux Kernel up to 5.12.12 cdc_eem eem_tx_fixup memory leak

| CVSS Meta Temp Score | Current Exploit Price (≈) | CTI Interest Score |
|---|---|---|
| 5.5 | $0-$5k | 0.00 |
Summary
A vulnerability, which was classified as critical, has been found in Linux Kernel up to 5.12.12. This affects the function eem_tx_fixup of the component cdc_eem. Performing a manipulation results in memory leak.
This vulnerability is reported as CVE-2021-47236. No exploit exists.
It is advisable to upgrade the affected component.
Details
A vulnerability classified as critical has been found in Linux Kernel up to 5.12.12. This affects the function eem_tx_fixup of the component cdc_eem. The manipulation with an unknown input leads to a memory leak vulnerability. CWE is classifying the issue as CWE-401. The product does not sufficiently track and release allocated memory after it has been used, which slowly consumes remaining memory. This is going to have an impact on availability. The summary by CVE is:
In the Linux kernel, the following vulnerability has been resolved: net: cdc_eem: fix tx fixup skb leak when usbnet transmit a skb, eem fixup it in eem_tx_fixup(), if skb_copy_expand() failed, it return NULL, usbnet_start_xmit() will have no chance to free original skb. fix it by free orginal skb in eem_tx_fixup() first, then check skb clone status, if failed, return NULL to usbnet.
It is possible to read the advisory at git.kernel.org. This vulnerability is uniquely identified as CVE-2021-47236 since 04/10/2024. Technical details of the vulnerability are known, but there is no available exploit.
Upgrading to version 4.4.274, 4.9.274, 4.14.238, 4.19.196, 5.4.128, 5.10.46 or 5.12.13 eliminates this vulnerability. Applying the patch f12554b0ff63/14184ec5c958/1bcacd6088d6/f4e6a7f19c82/81de2ed06df8/05b2b9f7d24b/b4f7a9fc9d09/c3b26fdf1b32 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.
Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.
Product
Type
Vendor
Name
Version
- 4.4.273
- 4.9.273
- 4.14.237
- 4.19.195
- 5.4.127
- 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
- 5.12.0
- 5.12.1
- 5.12.2
- 5.12.3
- 5.12.4
- 5.12.5
- 5.12.6
- 5.12.7
- 5.12.8
- 5.12.9
- 5.12.10
- 5.12.11
- 5.12.12
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 4.4.274/4.9.274/4.14.238/4.19.196/5.4.128/5.10.46/5.12.13
Patch: f12554b0ff63/14184ec5c958/1bcacd6088d6/f4e6a7f19c82/81de2ed06df8/05b2b9f7d24b/b4f7a9fc9d09/c3b26fdf1b32
Timeline
04/10/2024 🔍05/21/2024 🔍
05/21/2024 🔍
04/30/2025 🔍
Sources
Vendor: kernel.orgAdvisory: git.kernel.org
Status: Confirmed
CVE: CVE-2021-47236 (🔍)
GCVE (CVE): GCVE-0-2021-47236
GCVE (VulDB): GCVE-100-265707
Entry
Created: 05/21/2024 20:24Updated: 04/30/2025 09:34
Changes: 05/21/2024 20:24 (58), 04/30/2025 09:34 (12)
Complete: 🔍
Cache ID: 216::103
Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.
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