Vulnerability-Lookup

FKIE_CVE-2021-47427

Vulnerability from fkie_nvd - Published: 2024-05-21 15:15 - Updated: 2026-08-04 10:17

Severity

9.8 (Critical) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
7.8 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Summary

In the Linux kernel, the following vulnerability has been resolved: scsi: iscsi: Fix iscsi_task use after free Commit d39df158518c ("scsi: iscsi: Have abort handler get ref to conn") added iscsi_get_conn()/iscsi_put_conn() calls during abort handling but then also changed the handling of the case where we detect an already completed task where we now end up doing a goto to the common put/cleanup code. This results in a iscsi_task use after free, because the common cleanup code will do a put on the iscsi_task. This reverts the goto and moves the iscsi_get_conn() to after we've checked if the iscsi_task is valid.

References

URL	Tags
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/1642f51ac0d4f2b55d5748094c49ff8f7191b93c	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/258aad75c62146453d03028a44f2f1590d58e1f6	Patch
af854a3a-2127-422b-91ae-364da2661108	https://git.kernel.org/stable/c/1642f51ac0d4f2b55d5748094c49ff8f7191b93c	Patch
af854a3a-2127-422b-91ae-364da2661108	https://git.kernel.org/stable/c/258aad75c62146453d03028a44f2f1590d58e1f6	Patch

Impacted products

Vendor	Product	Version
linux	linux_kernel	*
linux	linux_kernel	5.15
linux	linux_kernel	5.15
linux	linux_kernel	5.15
linux	linux_kernel	5.15

JSON

To clipboard

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  "affected": [
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      "affectedData": [
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          "defaultStatus": "unaffected",
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          "programFiles": [
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      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nscsi: iscsi: Fix iscsi_task use after free\n\nCommit d39df158518c (\"scsi: iscsi: Have abort handler get ref to conn\")\nadded iscsi_get_conn()/iscsi_put_conn() calls during abort handling but\nthen also changed the handling of the case where we detect an already\ncompleted task where we now end up doing a goto to the common put/cleanup\ncode. This results in a iscsi_task use after free, because the common\ncleanup code will do a put on the iscsi_task.\n\nThis reverts the goto and moves the iscsi_get_conn() to after we\u0027ve checked\nif the iscsi_task is valid."
    },
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      "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: scsi: iscsi: corrige el uso after free de iscsi_task. Confirmaci\u00f3n d39df158518c (\"scsi: iscsi: Have abort handler get ref to conn\") se agregaron llamadas iscsi_get_conn()/iscsi_put_conn() durante el manejo de abortos pero luego tambi\u00e9n cambi\u00f3 el manejo del caso en el que detectamos una tarea ya completada y ahora terminamos haciendo un acceso al c\u00f3digo com\u00fan de put/cleanup. Esto da como resultado un uso de iscsi_task despu\u00e9s de la liberaci\u00f3n, porque el c\u00f3digo de limpieza com\u00fan colocar\u00e1 iscsi_task. Esto revierte el ir a y mueve iscsi_get_conn() a despu\u00e9s de haber verificado si iscsi_task es v\u00e1lido."
    }
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  "lastModified": "2026-08-04T10:17:02.990",
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          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
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          "userInteraction": "NONE",
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  "vulnStatus": "Modified",
  "weaknesses": [
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  ]
}

CVE-2021-47427 (GCVE-0-2021-47427)

Vulnerability from cvelistv5 – Published: 2024-05-21 15:04 – Updated: 2026-08-05 08:47

Title

scsi: iscsi: Fix iscsi_task use after free

Summary

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 2024-09-10 15:37 UTC

Assigner

Linux CNA under the mitre root

CNA scorecard D 53/100 over 6843 records in the last 180 days details

References

2 references

URL	Tags
https://git.kernel.org/stable/c/1642f51ac0d4f2b55…
https://git.kernel.org/stable/c/258aad75c62146453…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: d39df158518ccc3bf24ee18082b5e100c8f014aa , < 1642f51ac0d4f2b55d5748094c49ff8f7191b93c (git) Affected: d39df158518ccc3bf24ee18082b5e100c8f014aa , < 258aad75c62146453d03028a44f2f1590d58e1f6 (git)
Linux	Linux	Affected: 5.14 Unaffected: 0 , < 5.14 (semver) Unaffected: 5.14.12 , ≤ 5.14.* (semver) Unaffected: 5.15 , ≤ * (original_commit_for_fix)

Show details on NVD website

JSON

To clipboard

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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.

Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

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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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