Vulnerability CVE-2020-28020

Vulnerability Name:

CVE-2020-28020 (CCN-201193)

Assigned:

2020-10-30

Published:

2021-05-04

Updated:

2021-09-03

Summary:

Exim 4 before 4.92 allows Integer Overflow to Buffer Overflow, in which an unauthenticated remote attacker can execute arbitrary code by leveraging the mishandling of continuation lines during header-length restriction.

CVSS v3 Severity:

9.8 Critical (CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H)
8.9 High (Temporal CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:P/RL:U/RC:R)

Exploitability Metrics:	Attack Vector (AV): Network Attack Complexity (AC): Low Privileges Required (PR): None User Interaction (UI): None
Scope:	Scope (S): Unchanged
Impact Metrics:	Confidentiality (C): High Integrity (I): High Availibility (A): High

9.8 Critical (CCN CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H)
8.9 High (CCN Temporal CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:P/RL:U/RC:R)

Exploitability Metrics:	Attack Vector (AV): Network Attack Complexity (AC): Low Privileges Required (PR): None User Interaction (UI): None
Scope:	Scope (S): Unchanged
Impact Metrics:	Confidentiality (C): High Integrity (I): High Availibility (A): High

CVSS v2 Severity:

7.5 High (CVSS v2 Vector: AV:N/AC:L/Au:N/C:P/I:P/A:P)

Exploitability Metrics:	Access Vector (AV): Network Access Complexity (AC): Low Authentication (Au): None
Impact Metrics:	Confidentiality (C): Partial Integrity (I): Partial Availibility (A): Partial

10.0 High (CCN CVSS v2 Vector: AV:N/AC:L/Au:N/C:C/I:C/A:C)

Exploitability Metrics:	Access Vector (AV): Network Access Complexity (AC): Low Athentication (Au): None
Impact Metrics:	Confidentiality (C): Complete Integrity (I): Complete Availibility (A): Complete

Vulnerability Type:

CWE-190
CWE-120

Vulnerability Consequences:

Gain Access

References:

Source: MITRE
Type: CNA
CVE-2020-28020

Source: MLIST
Type: Mailing List, Third Party Advisory
[oss-security] 20210725 CVE-2020-28020: Integer overflow in Exim that can lead to RCE: Some questions to the Qualys researchers who designed the exploit

Source: MLIST
Type: Mailing List, Third Party Advisory
[oss-security] 20210802 Re: CVE-2020-28020: Integer overflow in Exim that can lead to RCE: Some questions to the Qualys researchers who designed the exploit

Source: XF
Type: UNKNOWN
exim-cve202028020-integer-overflow(201193)

Source: CCN
Type: oss-sec Mailing List, Tue, 4 May 2021 13:50:13 +0000
21Nails: Multiple vulnerabilities in Exim

Source: CCN
Type: Exim Web site
Exim

Source: MISC
Type: Patch, Third Party Advisory
https://www.exim.org/static/doc/security/CVE-2020-qualys/CVE-2020-28020-HSIZE.txt

Vulnerable Configuration:

Configuration 1:

cpe:/a:exim:exim:*:*:*:*:*:*:*:* (Version >= 4.00 and < 4.92)

Configuration CCN 1:

cpe:/a:exim:exim:*:*:*:*:*:*:*:*

Denotes that component is vulnerable

Oval Definitions

Definition ID	Class	Title	Last Modified
oval:org.opensuse.security:def:112207	P	exim-4.94.2-4.2 on GA media (Moderate)	2022-01-17
oval:org.opensuse.security:def:100366	P	(Moderate)	2021-12-16
oval:org.opensuse.security:def:105738	P	exim-4.94.2-4.2 on GA media (Moderate)	2021-10-01
oval:org.opensuse.security:def:93653	P	Security update for exim (Critical)	2021-05-20
oval:org.opensuse.security:def:109831	P	Security update for exim (Critical)	2021-05-20
oval:org.opensuse.security:def:96484	P	Security update for exim (Critical)	2021-05-20
oval:org.opensuse.security:def:11216	P	Security update for exim (Critical)	2021-05-20
oval:org.opensuse.security:def:11217	P	Security update for exim (Critical)	2021-05-20
oval:org.opensuse.security:def:103174	P	Security update for exim (Critical)	2021-05-20
oval:org.opensuse.security:def:107032	P	Security update for exim (Critical)	2021-05-20
oval:org.opensuse.security:def:111368	P	Security update for exim (Critical)	2021-05-07

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