CVE-2018-20843

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).

CVSS v3.0 7.5 HIGH
CVSS v2.0 7.8 HIGH

7.5^/10

CVSS v3.0 : HIGH

V3 Legend

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

7.8^/10

CVSS v2.0 : HIGH

V2 Legend

Vector : AV:N/AC:L/Au:N/C:N/I:N/A:C

Exploitability : 10.0 / Impact : 6.9

Access Vector NETWORK

Access Complexity LOW

Authentication NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact COMPLETE

References

Link	Resource
https://github.com/libexpat/libexpat/issues/186	Issue Tracking Patch Third Party Advisory
https://github.com/libexpat/libexpat/pull/262	Exploit Patch Third Party Advisory
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=5226	Issue Tracking Third Party Advisory
https://github.com/libexpat/libexpat/pull/262/commits/11f8838bf99ea0a6f0b76f9760c43704d00c4ff6	Patch Third Party Advisory
https://github.com/libexpat/libexpat/blob/R_2_2_7/expat/Changes	Release Notes Third Party Advisory
https://usn.ubuntu.com/4040-1/	Third Party Advisory
https://usn.ubuntu.com/4040-2/	Third Party Advisory
https://seclists.org/bugtraq/2019/Jun/39	Mailing List Third Party Advisory
https://www.debian.org/security/2019/dsa-4472	Third Party Advisory
https://lists.debian.org/debian-lts-announce/2019/06/msg00028.html	Mailing List Third Party Advisory
https://security.netapp.com/advisory/ntap-20190703-0001/	Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/CEJJSQSG3KSUQY4FPVHZ7ZTT7FORMFVD/	Mailing List Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/IDAUGEB3TUP6NEKJDBUBZX7N5OAUOOOK/	Mailing List Third Party Advisory
https://support.f5.com/csp/article/K51011533	Third Party Advisory
http://lists.opensuse.org/opensuse-security-announce/2019-07/msg00039.html	Mailing List Third Party Advisory
https://security.gentoo.org/glsa/201911-08	Third Party Advisory
https://www.oracle.com/security-alerts/cpuapr2020.html	Patch Third Party Advisory
https://www.oracle.com/security-alerts/cpuoct2020.html	Patch Third Party Advisory
https://www.oracle.com/security-alerts/cpuApr2021.html	Patch Third Party Advisory
https://www.tenable.com/security/tns-2021-11	Third Party Advisory
https://www.oracle.com/security-alerts/cpuoct2021.html	Patch Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:libexpat_project:libexpat:*:*:*:*:*:*:*:*

Configuration 2 (hide)

OR	cpe:2.3:o:canonical:ubuntu_linux:12.04::::-:::
	cpe:2.3:o:canonical:ubuntu_linux:14.04::::esm:::
	cpe:2.3:o:canonical:ubuntu_linux:16.04::::lts:::
	cpe:2.3:o:canonical:ubuntu_linux:18.04::::lts:::
	cpe:2.3:o:canonical:ubuntu_linux:18.10:::::::*
	cpe:2.3:o:canonical:ubuntu_linux:19.04:::::::*

Configuration 3 (hide)

OR	cpe:2.3:o:debian:debian_linux:8.0:::::::*
	cpe:2.3:o:debian:debian_linux:9.0:::::::*

Configuration 4 (hide)

OR	cpe:2.3:o:fedoraproject:fedora:29:::::::*
	cpe:2.3:o:fedoraproject:fedora:30:::::::*

Configuration 5 (hide)

OR	cpe:2.3:o:opensuse:leap:15.0:::::::*
	cpe:2.3:o:opensuse:leap:15.1:::::::*

Configuration 6 (hide)

OR	cpe:2.3:a:oracle:hospitality_res_3700::::::::
	cpe:2.3:a:oracle:http_server:12.1.3.0:::::::*
	cpe:2.3:a:oracle:http_server:12.2.1.4.0:::::::*
	cpe:2.3:a:oracle:outside_in_technology:8.5.4:::::::*
	cpe:2.3:a:oracle:outside_in_technology:8.5.5:::::::*

Configuration 7 (hide)

cpe:2.3:a:tenable:nessus:*:*:*:*:*:*:*:*

Information

Published : 2019-06-24 10:15

Updated : 2022-04-18 10:17

NVD link : CVE-2018-20843

Mitre link : CVE-2018-20843

JSON object : View

CWE

CWE-611

Improper Restriction of XML External Entity Reference

Products Affected

libexpat_project

libexpat

fedoraproject

fedora

canonical

ubuntu_linux

oracle

http_server
hospitality_res_3700
outside_in_technology

tenable

nessus

opensuse

leap

debian

debian_linux

{"cve": {"data_type": "CVE", "references": {"reference_data": [{"url": "https://github.com/libexpat/libexpat/issues/186", "name": "https://github.com/libexpat/libexpat/issues/186", "tags": ["Issue Tracking", "Patch", "Third Party Advisory"], "refsource": "MISC"}, {"url": "https://github.com/libexpat/libexpat/pull/262", "name": "https://github.com/libexpat/libexpat/pull/262", "tags": ["Exploit", "Patch", "Third Party Advisory"], "refsource": "MISC"}, {"url": "https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=5226", "name": "https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=5226", "tags": ["Issue Tracking", "Third Party Advisory"], "refsource": "MISC"}, {"url": "https://github.com/libexpat/libexpat/pull/262/commits/11f8838bf99ea0a6f0b76f9760c43704d00c4ff6", "name": "https://github.com/libexpat/libexpat/pull/262/commits/11f8838bf99ea0a6f0b76f9760c43704d00c4ff6", "tags": ["Patch", "Third Party Advisory"], "refsource": "MISC"}, {"url": "https://github.com/libexpat/libexpat/blob/R_2_2_7/expat/Changes", "name": "https://github.com/libexpat/libexpat/blob/R_2_2_7/expat/Changes", "tags": ["Release Notes", "Third Party Advisory"], "refsource": "MISC"}, {"url": "https://usn.ubuntu.com/4040-1/", "name": "USN-4040-1", "tags": ["Third Party Advisory"], "refsource": "UBUNTU"}, {"url": "https://usn.ubuntu.com/4040-2/", "name": "USN-4040-2", "tags": ["Third Party Advisory"], "refsource": "UBUNTU"}, {"url": "https://seclists.org/bugtraq/2019/Jun/39", "name": "20190628 [SECURITY] [DSA 4472-1] expat security update", "tags": ["Mailing List", "Third Party Advisory"], "refsource": "BUGTRAQ"}, {"url": "https://www.debian.org/security/2019/dsa-4472", "name": "DSA-4472", "tags": ["Third Party Advisory"], "refsource": "DEBIAN"}, {"url": "https://lists.debian.org/debian-lts-announce/2019/06/msg00028.html", "name": "[debian-lts-announce] 20190629 [SECURITY] [DLA 1839-1] expat security update", "tags": ["Mailing List", "Third Party Advisory"], "refsource": "MLIST"}, {"url": "https://security.netapp.com/advisory/ntap-20190703-0001/", "name": "https://security.netapp.com/advisory/ntap-20190703-0001/", "tags": ["Third Party Advisory"], "refsource": "CONFIRM"}, {"url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/CEJJSQSG3KSUQY4FPVHZ7ZTT7FORMFVD/", "name": "FEDORA-2019-18868e1715", "tags": ["Mailing List", "Third Party Advisory"], "refsource": "FEDORA"}, {"url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/IDAUGEB3TUP6NEKJDBUBZX7N5OAUOOOK/", "name": "FEDORA-2019-139fcda84d", "tags": ["Mailing List", "Third Party Advisory"], "refsource": "FEDORA"}, {"url": "https://support.f5.com/csp/article/K51011533", "name": "https://support.f5.com/csp/article/K51011533", "tags": ["Third Party Advisory"], "refsource": "CONFIRM"}, {"url": "http://lists.opensuse.org/opensuse-security-announce/2019-07/msg00039.html", "name": "openSUSE-SU-2019:1777", "tags": ["Mailing List", "Third Party Advisory"], "refsource": "SUSE"}, {"url": "https://security.gentoo.org/glsa/201911-08", "name": "GLSA-201911-08", "tags": ["Third Party Advisory"], "refsource": "GENTOO"}, {"url": "https://www.oracle.com/security-alerts/cpuapr2020.html", "name": "N/A", "tags": ["Patch", "Third Party Advisory"], "refsource": "N/A"}, {"url": "https://www.oracle.com/security-alerts/cpuoct2020.html", "name": "https://www.oracle.com/security-alerts/cpuoct2020.html", "tags": ["Patch", "Third Party Advisory"], "refsource": "MISC"}, {"url": "https://www.oracle.com/security-alerts/cpuApr2021.html", "name": "https://www.oracle.com/security-alerts/cpuApr2021.html", "tags": ["Patch", "Third Party Advisory"], "refsource": "MISC"}, {"url": "https://www.tenable.com/security/tns-2021-11", "name": "https://www.tenable.com/security/tns-2021-11", "tags": ["Third Party Advisory"], "refsource": "CONFIRM"}, {"url": "https://www.oracle.com/security-alerts/cpuoct2021.html", "name": "https://www.oracle.com/security-alerts/cpuoct2021.html", "tags": ["Patch", "Third Party Advisory"], "refsource": "MISC"}]}, "data_format": "MITRE", "description": {"description_data": [{"lang": "en", "value": "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)."}]}, "problemtype": {"problemtype_data": [{"description": [{"lang": "en", "value": "CWE-611"}]}]}, "data_version": "4.0", "CVE_data_meta": {"ID": "CVE-2018-20843", "ASSIGNER": "cve@mitre.org"}}, "impact": {"baseMetricV2": {"cvssV2": {"version": "2.0", "baseScore": 7.8, "accessVector": "NETWORK", "vectorString": "AV:N/AC:L/Au:N/C:N/I:N/A:C", "authentication": "NONE", "integrityImpact": "NONE", "accessComplexity": "LOW", "availabilityImpact": "COMPLETE", "confidentialityImpact": "NONE"}, "severity": "HIGH", "acInsufInfo": false, "impactScore": 6.9, "obtainAllPrivilege": false, "exploitabilityScore": 10.0, "obtainUserPrivilege": false, "obtainOtherPrivilege": false, "userInteractionRequired": false}, "baseMetricV3": {"cvssV3": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 7.5, "attackVector": "NETWORK", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "NONE", "confidentialityImpact": "NONE"}, "impactScore": 3.6, "exploitabilityScore": 3.9}}, "publishedDate": "2019-06-24T17:15Z", "configurations": {"nodes": [{"children": [], "operator": "OR", "cpe_match": [{"cpe23Uri": "cpe:2.3:a:libexpat_project:libexpat:*:*:*:*:*:*:*:*", "cpe_name": [], "vulnerable": true, "versionEndExcluding": "2.2.7"}]}, {"children": [], "operator": "OR", "cpe_match": [{"cpe23Uri": "cpe:2.3:o:canonical:ubuntu_linux:12.04:*:*:*:-:*:*:*", "cpe_name": [], "vulnerable": true}, {"cpe23Uri": "cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:esm:*:*:*", "cpe_name": [], "vulnerable": true}, {"cpe23Uri": "cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:lts:*:*:*", "cpe_name": [], "vulnerable": true}, {"cpe23Uri": "cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:*", "cpe_name": [], "vulnerable": true}, {"cpe23Uri": "cpe:2.3:o:canonical:ubuntu_linux:18.10:*:*:*:*:*:*:*", "cpe_name": [], "vulnerable": true}, {"cpe23Uri": "cpe:2.3:o:canonical:ubuntu_linux:19.04:*:*:*:*:*:*:*", "cpe_name": [], "vulnerable": true}]}, {"children": [], "operator": "OR", "cpe_match": [{"cpe23Uri": "cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*", "cpe_name": [], "vulnerable": true}, {"cpe23Uri": "cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*", "cpe_name": [], "vulnerable": true}]}, {"children": [], "operator": "OR", "cpe_match": [{"cpe23Uri": "cpe:2.3:o:fedoraproject:fedora:29:*:*:*:*:*:*:*", "cpe_name": [], "vulnerable": true}, {"cpe23Uri": "cpe:2.3:o:fedoraproject:fedora:30:*:*:*:*:*:*:*", "cpe_name": [], "vulnerable": true}]}, {"children": [], "operator": "OR", "cpe_match": [{"cpe23Uri": "cpe:2.3:o:opensuse:leap:15.0:*:*:*:*:*:*:*", "cpe_name": [], "vulnerable": true}, {"cpe23Uri": "cpe:2.3:o:opensuse:leap:15.1:*:*:*:*:*:*:*", "cpe_name": [], "vulnerable": true}]}, {"children": [], "operator": "OR", "cpe_match": [{"cpe23Uri": "cpe:2.3:a:oracle:hospitality_res_3700:*:*:*:*:*:*:*:*", "cpe_name": [], "vulnerable": true, "versionEndIncluding": "5.7.6", "versionStartIncluding": "5.7"}, {"cpe23Uri": "cpe:2.3:a:oracle:http_server:12.1.3.0:*:*:*:*:*:*:*", "cpe_name": [], "vulnerable": true}, {"cpe23Uri": "cpe:2.3:a:oracle:http_server:12.2.1.4.0:*:*:*:*:*:*:*", "cpe_name": [], "vulnerable": true}, {"cpe23Uri": "cpe:2.3:a:oracle:outside_in_technology:8.5.4:*:*:*:*:*:*:*", "cpe_name": [], "vulnerable": true}, {"cpe23Uri": "cpe:2.3:a:oracle:outside_in_technology:8.5.5:*:*:*:*:*:*:*", "cpe_name": [], "vulnerable": true}]}, {"children": [], "operator": "OR", "cpe_match": [{"cpe23Uri": "cpe:2.3:a:tenable:nessus:*:*:*:*:*:*:*:*", "cpe_name": [], "vulnerable": true, "versionEndExcluding": "8.15.0"}]}], "CVE_data_version": "4.0"}, "lastModifiedDate": "2022-04-18T17:17Z"}

7.5 /10

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

7.8 /10

Access Vector NETWORK

Access Complexity LOW

Authentication NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact COMPLETE

JSON object

Attach tags to CVE-2018-20843

7.5^/10

7.8^/10

Attach tags to `CVE-2018-20843`