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

Exim before 4.96 has an invalid free in pamconverse in auths/callpam.c because storefree is not used after storemalloc.

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.

A vulnerability was found in Exim and classified as problematic. This issue affects some unknown processing of the component Regex Handler. The manipulation leads to use after free. The name of the patch is 4e9ed49f8f12eb331b29bd5b6dc3693c520fddc2. It is recommended to apply a patch to fix this issue. The identifier VDB-211073 was assigned to this vulnerability.

Exim 4.88 before 4.99.4, in some proxy configurations, mishandles certain short payloads, leading to disclosure of uninitialized stack memory values to a client.

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.

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.

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.

[Exim NTLM Challenge Out-Of-Bounds Read Information Disclosure Vulnerability]

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

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

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

[Exim dnsdb Out-Of-Bounds Read Information Disclosure Vulnerability]

In Exim before 4.99.2, when utf8 operators are enabled, there is an out-of-bounds read if large UTF-8 trailing characters are present (malformed UTF-8 header data). Information might be divulged within an error message produced during handling of an unrelated e-mail message.

In Exim before 4.99.2, on systems using musl libc (not glibc), an attacker can crash the connection instance when malformed DNS data is present in PTR records. This is caused by a dnexpand oddity in octal printing.

Exim 4 before 4.94.2 allows Out-of-bounds Read. smtpsetupmsg may disclose sensitive information from process memory to an unauthenticated SMTP client.

Exim 4 before 4.94.2 allows Exposure of File Descriptor to Unintended Control Sphere because rdainterpret uses a privileged pipe that lacks a close-on-exec flag.

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.

Exim through 4.97.1 misparses a multiline RFC 2231 header filename, and thus remote attackers can bypass a $mimefilename extension-blocking protection mechanism, and potentially deliver executable attachments to the mailboxes of end users.

Exim 4 before 4.94.2 has Execution with Unnecessary Privileges. By leveraging a deletepidfile race condition, a local user can delete arbitrary files as root. This involves the -oP and -oPX options.

Exim 4 before 4.94.2 allows Heap-based Buffer Overflow because it mishandles "-F '.('" on the command line, and thus may allow privilege escalation from any user to root. This occurs because of the interpretation of negative sizes in strncpy.

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

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.

Exim 4 before 4.94.2 allows an off-by-two Out-of-bounds Write because "-F ''" is mishandled by parsefixphrase.

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.

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).

Exim 4 before 4.94.2 allows Integer Overflow to Buffer Overflow because getstdinput allows unbounded reads that are accompanied by unbounded increases in a certain size variable. NOTE: exploitation may be impractical because of the execution time needed to overflow (multiple days).

Exim 4 before 4.94.2 has Improper Neutralization of Line Delimiters. Local users can alter the behavior of root processes because a recipient address can have a newline character.

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.

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.