Vulnerability-Lookup

GHSA-3CH6-F277-559Q

Vulnerability from github – Published: 2024-02-28 09:30 – Updated: 2024-12-09 18:31

Details

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.

Severity

7.8 (High)


                  
                    CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

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{
  "affected": [],
  "aliases": [
    "CVE-2021-47013"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-416"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2024-02-28T09:15:38Z",
    "severity": "HIGH"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet:emac/emac-mac: Fix a use after free in emac_mac_tx_buf_send\n\nIn emac_mac_tx_buf_send, it calls emac_tx_fill_tpd(..,skb,..).\nIf some error happens in emac_tx_fill_tpd(), the skb will be freed via\ndev_kfree_skb(skb) in error branch of emac_tx_fill_tpd().\nBut the freed skb is still used via skb-\u003elen by netdev_sent_queue(,skb-\u003elen).\n\nAs i observed that emac_tx_fill_tpd() haven\u0027t modified the value of skb-\u003elen,\nthus my patch assigns skb-\u003elen to \u0027len\u0027 before the possible free and\nuse \u0027len\u0027 instead of skb-\u003elen later.",
  "id": "GHSA-3ch6-f277-559q",
  "modified": "2024-12-09T18:31:18Z",
  "published": "2024-02-28T09:30:38Z",
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    }
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}

CVE-2021-47013 (GCVE-0-2021-47013)

Vulnerability from cvelistv5 – Published: 2024-02-28 08:13 – Updated: 2026-08-05 08:45

Title

net:emac/emac-mac: Fix a use after free in emac_mac_tx_buf_send

Summary

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.

Severity

9.8 (Critical)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2024-02-28 19:56 UTC

Assigner

Linux mitre root Scorecard

References

8 references

URL	Tags
https://git.kernel.org/stable/c/c7f75d11fe72913d2…
https://git.kernel.org/stable/c/dc1b438a35773d030…
https://git.kernel.org/stable/c/16d8c44be52e36509…
https://git.kernel.org/stable/c/55fcdd1258faaecca…
https://git.kernel.org/stable/c/9dc373f74097edd0e…
https://git.kernel.org/stable/c/8c06f34785068b87e…
https://git.kernel.org/stable/c/e407495ba6788a67d…
https://git.kernel.org/stable/c/6d72e7c767acbbdd4…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: b9b17debc69d27cd55e21ee51a5ba7fc50a426cf , < c7f75d11fe72913d2619f97b2334b083cd7bb955 (git) Affected: b9b17debc69d27cd55e21ee51a5ba7fc50a426cf , < dc1b438a35773d030be0ee80d9c635c3e558a322 (git) Affected: b9b17debc69d27cd55e21ee51a5ba7fc50a426cf , < 16d8c44be52e3650917736d45f5904384a9da834 (git) Affected: b9b17debc69d27cd55e21ee51a5ba7fc50a426cf , < 55fcdd1258faaecca74b91b88cc0921f9edd775d (git) Affected: b9b17debc69d27cd55e21ee51a5ba7fc50a426cf , < 9dc373f74097edd0e35f3393d6248eda8d1ba99d (git) Affected: b9b17debc69d27cd55e21ee51a5ba7fc50a426cf , < 8c06f34785068b87e2b560534c77c163d6c6dca7 (git) Affected: b9b17debc69d27cd55e21ee51a5ba7fc50a426cf , < e407495ba6788a67d1bd41714158c079e340879b (git) Affected: b9b17debc69d27cd55e21ee51a5ba7fc50a426cf , < 6d72e7c767acbbdd44ebc7d89c6690b405b32b57 (git)
Linux	Linux	Affected: 4.9 Unaffected: 0 , < 4.9 (semver) Unaffected: 4.9.269 , ≤ 4.9.* (semver) Unaffected: 4.14.233 , ≤ 4.14.* (semver) Unaffected: 4.19.191 , ≤ 4.19.* (semver) Unaffected: 5.4.119 , ≤ 5.4.* (semver) Unaffected: 5.10.37 , ≤ 5.10.* (semver) Unaffected: 5.11.21 , ≤ 5.11.* (semver) Unaffected: 5.12.4 , ≤ 5.12.* (semver) Unaffected: 5.13 , ≤ * (original_commit_for_fix)

Show details on NVD website

JSON

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Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

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GHSA-3CH6-F277-559Q

CVE-2021-47013 (GCVE-0-2021-47013)

Tags

Sightings

Nomenclature

Related by attack behaviour