FKIE_CVE-2018-20843
Vulnerability from fkie_nvd - Published: 2019-06-24 17:15 - Updated: 2026-06-17 01:53
Severity
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
7.5 (High) - CVSS:3.1/
Summary
In libexpat in Expat before 2.2.7, XML input including XML names that contain a large number of colons could make the XML parser consume a high amount of RAM and CPU resources while processing (enough to be usable for denial-of-service attacks).
References
Impacted products
| Vendor | Product | Version | |
|---|---|---|---|
| libexpat_project | libexpat | * | |
| canonical | ubuntu_linux | 12.04 | |
| canonical | ubuntu_linux | 14.04 | |
| canonical | ubuntu_linux | 16.04 | |
| canonical | ubuntu_linux | 18.04 | |
| canonical | ubuntu_linux | 18.10 | |
| canonical | ubuntu_linux | 19.04 | |
| debian | debian_linux | 8.0 | |
| debian | debian_linux | 9.0 | |
| fedoraproject | fedora | 29 | |
| fedoraproject | fedora | 30 | |
| opensuse | leap | 15.0 | |
| opensuse | leap | 15.1 | |
| oracle | hospitality_res_3700 | * | |
| oracle | http_server | 12.1.3.0 | |
| oracle | http_server | 12.2.1.4.0 | |
| oracle | outside_in_technology | 8.5.4 | |
| oracle | outside_in_technology | 8.5.5 | |
| tenable | nessus | * |
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"value": "En libexpat en Expat anterior a versi\u00f3n 2.2.7, una entrada XML incluyendo nombres XML que contienen una gran cantidad de \"dos puntos\", podr\u00eda hacer que el analizador XML consuma una gran cantidad de recursos de RAM y CPU durante el procesamiento (lo suficiente como para ser utilizables en ataques de denegaci\u00f3n de servicio) ."
}
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"id": "CVE-2018-20843",
"lastModified": "2026-06-17T01:53:34.663",
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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.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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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