Gaël Delalleau

**Name of the Vulnerable Software and Affected Versions** Telnet clients versions (affected versions not specified) Red Hat Enterprise Linux telnet-server-0.17 Red Hat Enterprise Linux telnet-0.17 **Description** The issue allows remote malicious Telnet servers to read sensitive environment variables via the NEW-ENVIRON option with a SEND ENV USERVAR command. Exploitation of this issue can lead to a violation of confidentiality, integrity, and availability of protected information. The exploitation can be carried out remotely. **Recommendations** For Telnet clients, consider disabling the NEW-ENVIRON option to prevent the sending of sensitive environment variables until a patch is available. For Red Hat Enterprise Linux telnet-server-0.17 and telnet-0.17, at the moment, there is no information about a newer version that contains a fix for this vulnerability.

**Name of the Vulnerable Software and Affected Versions** Microsoft Exchange Server version 5.5 **Description** A cross-site scripting issue exists, allowing remote attackers to inject arbitrary web script or HTML via an email message with an encoded javascript: URL in an IMG tag. **Recommendations** For Microsoft Exchange Server version 5.5, at the moment, there is no information about a newer version that contains a fix for this vulnerability.

**Name of the Vulnerable Software and Affected Versions** Microsoft Windows XP Microsoft Windows Server 2003 Microsoft Windows Services for UNIX **Description** The issue allows remote attackers to read sensitive environment variables. This is achieved via the NEW-ENVIRON option with a SEND ENV USERVAR command in the Telnet client. **Recommendations** For Microsoft Windows XP, consider disabling the Telnet client until a fix is available. For Microsoft Windows Server 2003, restrict access to the Telnet service to minimize the risk of exploitation. For Microsoft Windows Services for UNIX, avoid using the Telnet client with the NEW-ENVIRON option until the issue is resolved.

**Name of the Vulnerable Software and Affected Versions** Telnet clients (affected versions not specified) **Description** A heap-based buffer overflow issue exists in the env opt add function in telnet.c for various BSD-based Telnet clients. This allows remote attackers to execute arbitrary code via responses that contain a large number of characters requiring escaping, which consumes more memory than allocated. **Recommendations** At the moment, there is no information about a newer version that contains a fix for this vulnerability.

**Name of the Vulnerable Software and Affected Versions** Mozilla versions 1.7.3 Firefox version 1.0 Thunderbird versions prior to 1.0.2 **Description** The issue is related to string handling functions, such as the `nsTSubstring CharT::Replace` function, which do not properly check the return values of other functions that resize the string. This allows remote attackers to cause a denial of service and possibly execute arbitrary code by forcing an out-of-memory state that causes a reallocation to fail and return a pointer to a fixed address, leading to heap corruption. **Recommendations** For Mozilla version 1.7.3, update to a version that includes the fix for this issue. For Firefox version 1.0, update to a version that includes the fix for this issue. For Thunderbird versions prior to 1.0.2, update to version 1.0.2 or later.