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Vendor Risk Score

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Severity
10
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Exim before 4.92.2 allows remote attackers to execute arbitrary code as root via a trailing backslash.

1 / 2
Source: Launchpad

Remedy

Add - as part of the mail ACL (the ACL referenced by the main config option "acl_smtp_mail"): deny condition = ${if eq{\\}{${substr{-1}{1}{$tls_in_sni}}}} deny condition = ${if eq{\\}{${substr{-1}{1}{$tls_in_peerdn}}}}
First published (updated )
Severity
10
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Exim 4.85 through 4.92 (fixed in 4.92.1) allows remote code execution as root in some unusual configurations that use the ${sort } expansion for items that can be controlled by an attacker (e.g., $localpart or $domain).

First published (updated )
Severity
9.8
Buffer Overflow
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

An issue was discovered in the base64d function in the SMTP listener in Exim before 4.90.1. By sending a handcrafted message, a buffer overflow may happen. This can be used to execute code remotely.

1 / 3
Source: Launchpad
First published (updated )
Severity
9.8
EPSS
33.96%
SQL Injection
AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Exim 4.98 before 4.98.1, when SQLite hints and ETRN serialization are used, allows remote SQL injection. (Resolving SQL injection requires an update to 4.99.1 in certain non-default rate-limit configurations.)

First published (updated )
Severity
9.8
Buffer Overflow
AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:H/A:L

Exim before 4.99.1, with certain non-default rate-limit configurations, allows a remote heap-based buffer overflow because database records are cast directly to internal structures without validation.

First published (updated )
Severity
9.8
AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:H

In Exim before 4.99.2, when JSON lookup is enabled, an out-of-bounds heap write can occur when a JSON operator encounters malformed JSON in an untrusted header, because of an incorrect implementation of \ skipping.

First published (updated )
Severity
9.8
Use After Free
AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Exim before 4.99.3, in certain GnuTLS configurations, has a remotely reachable use-after-free in the BDAT body parsing path. It is triggered when a client sends a TLS closenotify mid-body during a CHUNKING transfer, followed by a final cleartext byte on the same TCP connection. This can lead to heap corruption. An unauthenticated network attacker exploiting this vulnerability could execute arbitrary code.

First published (updated )
Severity
9.8
Buffer Overflow
AV:N/AC:M/Au:N/C:C/I:C/A:C

Heap-based buffer overflow in the stringvformat function in string.c in Exim before 4.70 allows remote attackers to execute arbitrary code via an SMTP session that includes two MAIL commands in conjunction with a large message containing crafted headers, leading to improper rejection logging.

1 / 3
First published (updated )
Severity
9.8
Buffer Overflow
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Exim 4.92 through 4.92.2 allows remote code execution, a different vulnerability than CVE-2019-15846. There is a heap-based buffer overflow in stringvformat in string.c involving a long EHLO command.

1 / 3
Source: Launchpad
First published (updated )
Severity
9.8
AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

This vulnerability allows remote attackers to execute arbitrary code on affected installations of Exim. Authentication is not required to exploit this vulnerability. The specific flaw exists within the smtp service, which listens on TCP port 25 by default. The issue results from the lack of proper validation of user-supplied data, which can result in a write past the end of a buffer. An attacker can leverage this vulnerability to execute code in the context of the service account.

1 / 2
Source: ZDI
First published (updated )
Severity
9.8
AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

This vulnerability allows remote attackers to execute arbitrary code on affected installations of Exim. Authentication is not required to exploit this vulnerability. The specific flaw exists within the smtp service, which listens on TCP port 25 by default. The issue results from the lack of proper validation of user-supplied data, which can result in a write past the end of a buffer. An attacker can leverage this vulnerability to execute code in the context of the service account.

1 / 2
Source: ZDI
First published (updated )
Advisory
ZDI-23-1469
Severity
9.8
AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

[Exim AUTH Out-Of-Bounds Write Remote Code Execution Vulnerability]

1 / 4
Source: Ubuntu
First published (updated )
Severity
9.8
Buffer Overflow
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

[Exim SMTP Challenge Stack-based Buffer Overflow Remote Code Execution Vulnerability]

1 / 5
Source: Ubuntu
First published (updated )
Severity
9.8
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Exim 4 before 4.94.2 has Improper Restriction of Write Operations within the Bounds of a Memory Buffer. This occurs when processing name=value pairs within MAIL FROM and RCPT TO commands.

First published (updated )
Severity
9.8
Buffer Overflow, Integer Overflow
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

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.

First published (updated )
Severity
9.8
Use After Free
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Exim 4 before 4.94.2 allows Use After Free in smtpreset in certain situations that may be common for builds with OpenSSL.

First published (updated )
Severity
9.8
Buffer Overflow, Integer Overflow
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Exim 4 before 4.94.2 allows Integer Overflow to Buffer Overflow in receiveaddrecipient via an e-mail message with fifty million recipients. NOTE: remote exploitation may be difficult because of resource consumption.

First published (updated )
Severity
9.8
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Exim 4 before 4.94.2 allows Buffer Underwrite that may result in unauthenticated remote attackers executing arbitrary commands, because smtpungetc was only intended to push back characters, but can actually push back non-character error codes such as EOF.

First published (updated )
Severity
9.8
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Exim 4 before 4.94.2 has Improper Neutralization of Line Delimiters, relevant in non-default configurations that enable Delivery Status Notification (DSN). Certain uses of ORCPT= can place a newline into a spool header file, and indirectly allow unauthenticated remote attackers to execute arbitrary commands as root.

First published (updated )
Severity
9.8
Use After Free
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

The receivemsg function in receive.c in the SMTP daemon in Exim 4.88 and 4.89 allows remote attackers to execute arbitrary code or cause a denial of service (use-after-free) via vectors involving BDAT commands.

First published (updated )
Severity
9.8
OS Command Injection
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

A flaw was found in Exim versions 4.87 to 4.91 (inclusive). Improper validation of recipient address in delivermessage() function in /src/deliver.c may lead to remote command execution.

1 / 3
Source: Launchpad
First published (updated )
Severity
9.8
Buffer Overflow
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Exim before 4.95 has a heap-based buffer overflow for the alias list in hostnamelookup in host.c when senderhostname is set.

First published (updated )
Severity
9.8
Buffer Overflow, Use After Free
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

A vulnerability was found in Exim and classified as problematic. This issue affects the function dmarcdnslookup of the file dmarc.c of the component DMARC Handler. The manipulation leads to use after free. The attack may be initiated remotely. The name of the patch is 12fb3842f81bcbd4a4519d5728f2d7e0e3ca1445. It is recommended to apply a patch to fix this issue. The associated identifier of this vulnerability is VDB-211919.

First published (updated )
Severity
9.8
AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

[Exim Improper Neutralization of Special Elements Remote Code Execution Vulnerability]

1 / 4
Source: Ubuntu
First published (updated )
Severity
9.1
AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:L

In Exim before 4.99.2, when the SPA authentication driver is used with an adversarial SPA resource, there can be an out-of-bounds write that crashes the connection instance, or erroneous data processing that divulges data from uninitialized heap memory.

First published (updated )
Severity
9
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Exim 4 before 4.94.2 has Improper Neutralization of Line Delimiters. An authenticated remote SMTP client can insert newline characters into a spool file (which indirectly leads to remote code execution as root) via AUTH= in a MAIL FROM command.

First published (updated )
Severity
8.8
Integer Underflow
AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

Exim libspf2 Integer Underflow Remote Code Execution Vulnerability. This vulnerability allows network-adjacent attackers to execute arbitrary code on affected installations of Exim libspf2. Authentication is not required to exploit this vulnerability.

The specific flaw exists within the parsing of SPF macros. When parsing SPF macros, the process does not properly validate user-supplied data, which can result in an integer underflow before writing to memory. An attacker can leverage this vulnerability to execute code in the context of the service account. . Was ZDI-CAN-17578.

1 / 2
Source: MITRE
First published (updated )
Severity
8.4
AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Exim before 4.99.5 allows directory traversal to access files outside of the spool area, and consequently gain privileges, because arguments related to queue-name are mishandled.

First published (updated )
Severity
8.4
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

A UNIX Symbolic Link (Symlink) Following vulnerability in the packaging of exim in openSUSE Factory allows local attackers to escalate from user mail to root. This issue affects: openSUSE Factory exim versions prior to 4.93.0.4-3.1.

First published (updated )
Severity
8.1
EPSS
0.03%
Use After Free
AV:L/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H

A use-after-free in Exim 4.96 through 4.98.1 could allow users (with command-line access) to escalate privileges.

First published (updated )

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