OpenSMTPD Remote Command Execution via SMTP MAIL FROM
Actively exploited in the wild. Patch or mitigate immediately — don't wait for a maintenance window.
An unauthenticated attacker, remotely over the network, with no user interaction, can fully compromise the system — steal data, tamper with it and take it offline.
smtp_mailaddr in smtp_session.c in OpenSMTPD 6.6, as used in OpenBSD 6.6 and other products, allows remote attackers to execute arbitrary commands as root via a crafted SMTP session, as demonstrated by shell metacharacters in a MAIL FROM field. This affects the "uncommented" default configuration. The issue exists because of an incorrect return value upon failure of input validation.
Inferred from the weakness type (CWE) and how the flaw is reached — the techniques an attacker would chain to exploit this. Real-world corroboration appears here as threat intel is folded in.
Corroborated threat activity referencing this CVE — with source and confidence, not inference.
Named threat actors and observed ATT&CK techniques appear here as intel feeds are folded in — the ATT&CK chain above stays inferred until then.
Generated by Wavense from the CVE record — an immediate mitigation and the permanent fix.
Temporarily restrict direct internet access to the OpenSMTPD service using firewall rules, allowing connections only from trusted internal systems or a secure SMTP gateway. Implement an SMTP proxy or gateway that performs rigorous input validation on all incoming SMTP commands, specifically scrutinizing the MAIL FROM field for shell metacharacters. Enhance logging and monitoring for unusual activity or malformed requests on the SMTP port, such as connections attempting suspicious characters.
The permanent resolution is to immediately upgrade OpenSMTPD to a patched version, specifically OpenSMTPD 6.6.2p1 or later. For OpenBSD users, ensure the system is updated to a release containing this fix, or manually apply the necessary patches. Verify the upgrade by checking the OpenSMTPD version and confirming the vulnerability is no longer present in the configuration.
This critical vulnerability allows remote unauthenticated attackers to execute arbitrary commands as the 'root' user on affected OpenSMTPD instances. Successful exploitation grants complete control over the compromised system, enabling data exfiltration, service disruption, and the deployment of additional malicious payloads. The business consequences include severe data breaches, loss of system integrity, and potential regulatory fines due to a full system compromise.
Other CVEs affecting ubuntu linux
Erlang/OTP is a set of libraries for the Erlang programming language. Prior to versions OTP-27.3.3, OTP-26.2.5.11, and OTP-25.3.2.20, a SSH server may allow an attacker to perform unauthenticated remote code execution (RCE). By exploiting a flaw in SSH protocol message handling, a malicious actor could gain unauthorized access to affected systems and execute arbitrary commands without valid credentials. This issue is patched in versions OTP-27.3.3, OTP-26.2.5.11, and OTP-25.3.2.20. A temporary workaround involves disabling the SSH server or to prevent access via firewall rules.
An out-of-bounds write issue was addressed with improved checks to prevent unauthorized actions. This issue is fixed in Safari 18.3.1, iOS 15.8.4 and iPadOS 15.8.4, iOS 16.7.11 and iPadOS 16.7.11, iOS 18.3.2 and iPadOS 18.3.2, iPadOS 17.7.6, macOS Sequoia 15.3.2, visionOS 2.3.2, watchOS 11.4. Maliciously crafted web content may be able to break out of Web Content sandbox. This is a supplementary fix for an attack that was blocked in iOS 17.2. (Apple is aware of a report that this issue may have been exploited in an extremely sophisticated attack against specific targeted individuals on versions of iOS before iOS 17.2.).
The Java OpenWire protocol marshaller is vulnerable to Remote Code Execution. This vulnerability may allow a remote attacker with network access to either a Java-based OpenWire broker or client to run arbitrary shell commands by manipulating serialized class types in the OpenWire protocol to cause either the client or the broker (respectively) to instantiate any class on the classpath. Users are recommended to upgrade both brokers and clients to version 5.15.16, 5.16.7, 5.17.6, or 5.18.3 which fixes this issue.
The mod_copy module in ProFTPD 1.3.5 allows remote attackers to read and write to arbitrary files via the site cpfr and site cpto commands.
Roundcube Webmail before 1.5.10 and 1.6.x before 1.6.11 allows remote code execution by authenticated users because the _from parameter in a URL is not validated in program/actions/settings/upload.php, leading to PHP Object Deserialization.
telnetd in GNU Inetutils through 2.7 allows remote authentication bypass via a "-f root" value for the USER environment variable.
In the Linux kernel, the following vulnerability has been resolved: tls: fix handling of zero-length records on the rx_list Each recvmsg() call must process either - only contiguous DATA records (any number of them) - one non-DATA record If the next record has different type than what has already been processed we break out of the main processing loop. If the record has already been decrypted (which may be the case for TLS 1.3 where we don't know type until decryption) we queue the pending record to the rx_list. Next recvmsg() will pick it up from there. Queuing the skb to rx_list after zero-copy decrypt is not possible, since in that case we decrypted directly to the user space buffer, and we don't have an skb to queue (darg.skb points to the ciphertext skb for access to metadata like length). Only data records are allowed zero-copy, and we break the processing loop after each non-data record. So we should never zero-copy and then find out that the record type has changed. The corner case we missed is when the initial record comes from rx_list, and it's zero length.
Path Equivalence: 'file.Name' (Internal Dot) leading to Remote Code Execution and/or Information disclosure and/or malicious content added to uploaded files via write enabled Default Servlet in Apache Tomcat. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.2, from 10.1.0-M1 through 10.1.34, from 9.0.0.M1 through 9.0.98. The following versions were EOL at the time the CVE was created but are known to be affected: 8.5.0 though 8.5.100. Other, older, EOL versions may also be affected. If all of the following were true, a malicious user was able to view security sensitive files and/or inject content into those files: - writes enabled for the default servlet (disabled by default) - support for partial PUT (enabled by default) - a target URL for security sensitive uploads that was a sub-directory of a target URL for public uploads - attacker knowledge of the names of security sensitive files being uploaded - the security sensitive files also being uploaded via partial PUT If all of the following were true, a malicious user was able to perform remote code execution: - writes enabled for the default servlet (disabled by default) - support for partial PUT (enabled by default) - application was using Tomcat's file based session persistence with the default storage location - application included a library that may be leveraged in a deserialization attack Users are recommended to upgrade to version 11.0.3, 10.1.35 or 9.0.99, which fixes the issue.