CVE-2021-47013

Advisory lineage Upstream: 0 Downstream: 14
Analyzed
Published: 28 Feb 2024, 08:13
Last modified:11 May 2026, 13:46

Vulnerability Summary

Overall Risk (default)
medium
31/100
CVSS Score
7.8 HIGH
v3.1 (nvd)
EPSS Score
0.01% LOW
0% probability 0.00%
KEV
Not listed
Ransomware
No reports
Public exploits
None found
Dark Web
Not detected

Timeline

28 Feb 2024, 08:13
Published
Vulnerability first disclosed
11 May 2026, 13:46
Last Modified
Vulnerability information updated

Description

In the Linux kernel, the following vulnerability has been resolved: net:emac/emac-mac: Fix a use after free in emac_mac_tx_buf_send In emac_mac_tx_buf_send, it calls emac_tx_fill_tpd(..,skb,..). If some error happens in emac_tx_fill_tpd(), the skb will be freed via dev_kfree_skb(skb) in error branch of emac_tx_fill_tpd(). But the freed skb is still used via skb->len by netdev_sent_queue(,skb->len). As i observed that emac_tx_fill_tpd() haven't modified the value of skb->len, thus my patch assigns skb->len to 'len' before the possible free and use 'len' instead of skb->len later.

CVSS Metrics

  • v3.1•HIGH•Score: 7.8CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

EPSS Trends

Current EPSS score: 0.01%• Percentile: 3%

Techniques & Countermeasures

  • CWE-416•Use After Free

    The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer.

Affected Systems

  • linux•linux

    ≥ b9b17debc69d27cd55e21ee51a5ba7fc50a426cf, < c7f75d11fe72913d2619f97b2334b083cd7bb955 | ≥ b9b17debc69d27cd55e21ee51a5ba7fc50a426cf, < dc1b438a35773d030be0ee80d9c635c3e558a322 | ≥ b9b17debc69d27cd55e21ee51a5ba7fc50a426cf, < 16d8c44be52e3650917736d45f5904384a9da834 | ≥ b9b17debc69d27cd55e21ee51a5ba7fc50a426cf, < 55fcdd1258faaecca74b91b88cc0921f9edd775d | ≥ b9b17debc69d27cd55e21ee51a5ba7fc50a426cf, < 9dc373f74097edd0e35f3393d6248eda8d1ba99d | ≥ b9b17debc69d27cd55e21ee51a5ba7fc50a426cf, < 8c06f34785068b87e2b560534c77c163d6c6dca7 | ≥ b9b17debc69d27cd55e21ee51a5ba7fc50a426cf, < e407495ba6788a67d1bd41714158c079e340879b | ≥ b9b17debc69d27cd55e21ee51a5ba7fc50a426cf, < 6d72e7c767acbbdd44ebc7d89c6690b405b32b57 | 4.9

  • linux•linux_kernel

    ≥ 4.9, < 4.9.269 | ≥ 4.10, < 4.14.233 | ≥ 4.15, < 4.19.191 | ≥ 4.20, < 5.4.119 | ≥ 5.5, < 5.10.37 | ≥ 5.11, < 5.11.21 | ≥ 5.12, < 5.12.4

References (8)