CVE-2021-36386

fetchmail: DoS or information disclosure when logging long messages

Severity Score

7.5

*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

*Multiple Sources

Exploited in Wild

*KEV

Decision

*SSVC

Descriptions

report_vbuild in report.c in Fetchmail before 6.4.20 sometimes omits initialization of the vsnprintf va_list argument, which might allow mail servers to cause a denial of service or possibly have unspecified other impact via long error messages. NOTE: it is unclear whether use of Fetchmail on any realistic platform results in an impact beyond an inconvenience to the client user.

Una función report_vbuild en el archivo report.c en Fetchmail versiones anteriores a 6.4.20, a veces omite la inicialización del argumento vsnprintf va_list, lo que podría permitir a servidores de correo causar una denegación de servicio o posiblemente tener otro impacto no especificado por medio de largos mensajes de error. NOTA: no está claro si el uso de Fetchmail en cualquier plataforma realista presenta un impacto más allá de un inconveniente para el usuario cliente

A flaw was found in fetchmail. The flaw lies in how fetchmail when running in verbose mode using the -v flag tries to log long messages that are created from long headers. An attacker could potentially use this flaw to cause a Denial of Service attack or crash. The highest threat from this vulnerability is to data availability. This flaw was earlier identified by CVE-2008-2711 and fixed, however it recently got reintroduced due to a code refactoring issue. The current bug fix applies a different approach than the earlier one.

*Credits: N/A

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

Attack Vector

Network

Attack Complexity

Low

Authentication

None

Confidentiality

None

Integrity

None

Availability

Partial

* Common Vulnerability Scoring System

SSVC

Decision:-

Exploitation

Automatable

Tech. Impact

* Organization's Worst-case Scenario

Timeline

2021-07-12 CVE Reserved
2021-07-29 CVE Published
2024-04-13 EPSS Updated
2024-08-04 CVE Updated
---------- Exploited in Wild
---------- KEV Due Date
---------- First Exploit

CWE

CWE-665: Improper Initialization
CWE-909: Missing Initialization of Resource

CAPEC

References (9)

URL	Tag	Source
http://www.openwall.com/lists/oss-security/2021/08/09/1	Mailing List

URL	Date	SRC

URL	Date	SRC
http://www.openwall.com/lists/oss-security/2021/07/28/5	2023-11-07

URL	Date	SRC
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/AGYO5AHSXTCKA4NQC2Z4H3XMMYNAGC77	2023-11-07
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/OIXKO6QW3AUHGJVWKJXBCOVBYJUJRBFC	2023-11-07
https://security.gentoo.org/glsa/202209-14	2023-11-07
https://www.fetchmail.info/fetchmail-SA-2021-01.txt	2023-11-07
https://www.fetchmail.info/security.html	2023-11-07
https://access.redhat.com/security/cve/CVE-2021-36386	2022-05-10
https://bugzilla.redhat.com/show_bug.cgi?id=1987766	2022-05-10

Affected Vendors, Products, and Versions

Vendor		Product				Version		Other		Status
Vendor	Product	Version	Other	Status	<-- -->	Vendor	Product	Version	Other	Status
Fetchmail Search vendor "Fetchmail"		Fetchmail Search vendor "Fetchmail" for product "Fetchmail"				< 6.4.20 Search vendor "Fetchmail" for product "Fetchmail" and version " < 6.4.20"		-		Affected
Fedoraproject Search vendor "Fedoraproject"		Fedora Search vendor "Fedoraproject" for product "Fedora"				33 Search vendor "Fedoraproject" for product "Fedora" and version "33"		-		Affected
Fedoraproject Search vendor "Fedoraproject"		Fedora Search vendor "Fedoraproject" for product "Fedora"				34 Search vendor "Fedoraproject" for product "Fedora" and version "34"		-		Affected