CVE-2021-4145 (GCVE-0-2021-4145)
Vulnerability from cvelistv5 – Published: 2022-01-25 19:11 – Updated: 2024-08-03 17:16
VLAI
EPSS
VEX
Summary
A NULL pointer dereference issue was found in the block mirror layer of QEMU in versions prior to 6.2.0. The `self` pointer is dereferenced in mirror_wait_on_conflicts() without ensuring that it's not NULL. A malicious unprivileged user within the guest could use this flaw to crash the QEMU process on the host when writing data reaches the threshold of mirroring node.
Severity
6.5 (Medium)
CWE
Assigner
References
4 references
| URL | Tags |
|---|---|
| https://bugzilla.redhat.com/show_bug.cgi?id=2034602 | x_refsource_MISC |
| https://gitlab.com/qemu-project/qemu/-/commit/66f… | x_refsource_MISC |
| https://security.netapp.com/advisory/ntap-2022031… | x_refsource_CONFIRM |
| https://security.gentoo.org/glsa/202208-27 | vendor-advisoryx_refsource_GENTOO |
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"source": "Red Hat CSAF VEX",
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"title": "QEMU: NULL pointer dereference in mirror_wait_on_conflicts() in block/mirror.c",
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"cve": "CVE-2021-4145",
"id": "CVE-2021-4145",
"initial_release_date": "2023-02-15T03:47:55Z",
"product_status:known_not_affected": "1069",
"source": "SUSE CSAF VEX",
"status": "interim",
"title": "SUSE CVE CVE-2021-4145",
"url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2021-4145.json",
"version": "12"
}
}
}
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
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.
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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.
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.
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