Vulnerability-Lookup

GSD-2021-20219

Vulnerability from gsd - Updated: 2023-12-13 01:23

Details

A denial of service vulnerability was found in n_tty_receive_char_special in drivers/tty/n_tty.c of the Linux kernel. In this flaw a local attacker with a normal user privilege could delay the loop (due to a changing ldata->read_head, and a missing sanity check) and cause a threat to the system availability.

Aliases

CVE-2021-20219

Aliases

CVE-2021-20219

JSON

To clipboard

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    "description": "A denial of service vulnerability was found in n_tty_receive_char_special in drivers/tty/n_tty.c of the Linux kernel. In this flaw a local attacker with a normal user privilege could delay the loop (due to a changing ldata-\u003eread_head, and a missing sanity check) and cause a threat to the system availability.",
    "id": "GSD-2021-20219",
    "references": [
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      "https://linux.oracle.com/cve/CVE-2021-20219.html"
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}

CVE-2021-20219 (GCVE-0-2021-20219)

Vulnerability from cvelistv5 – Published: 2021-03-23 16:34 – Updated: 2024-08-03 17:30

Summary

Severity

No CVSS data available.

CWE

CWE-697

Assigner

redhat redhat root

References

1 reference

URL	Tags
https://bugzilla.redhat.com/show_bug.cgi?id=1923738	x_refsource_MISC

Impacted products

1 product

Vendor	Product	Version
n/a	kernel	Affected: kernel 4.18

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.

Detection rules are retrieved from Rulezet.

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.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.