Multiple stack-based buffer overflows in Yahoo! Messenger 11.5.0.228 and earlier allow remote attackers to cause a denial of service (crash) and possibly execute arbitrary code via the (1) shortcut or (2) title keys in an emoticons.xml file.

Integer overflow in the CYImage::LoadJPG method in YImage.dll in Yahoo! Messenger before 11.5.0.155, when photo sharing is enabled, might allow remote attackers to execute arbitrary code via a crafted JPG image that triggers a heap-based buffer overflow.

Buffer overflow in a certain ActiveX control in YVerInfo.dll before 2007.8.27.1 in the Yahoo! services suite for Yahoo! Messenger before 8.1.0.419 allows remote attackers to execute arbitrary code via unspecified vectors involving arguments to the (1) fvCom and (2) info methods. NOTE: some of these details are obtained from third party information.

Unspecified vulnerability in the Chat Room functionality in Yahoo! Messenger 8.1.0.239 and earlier allows remote attackers to cause a denial of service via unspecified vectors. NOTE: the provenance of this information is unknown; the details are obtained solely from third party information.

Multiple cross-site scripting (XSS) vulnerabilities in the Contact Details functionality in Yahoo! Messenger 8.1.0.209 and earlier allow user-assisted remote attackers to inject arbitrary web script or HTML via a javascript: URI in the SRC attribute of an IMG element to the (1) First Name, (2) Last Name, and (3) Nickname fields. NOTE: some of these details are obtained from third party information.

Buffer overflow in the YMMAPI.YMailAttach ActiveX control (ymmapi.dll) before 2005.1.1.4 in Yahoo! Messenger allows remote attackers to execute arbitrary code via a crafted HTML document. NOTE: some details were obtained from third party information.

Yahoo! Messenger for WAP permits saving messages that contain JavaScript, which allows user-assisted remote attackers to inject arbitrary web script or HTML via a URL at the online service.

Buffer overflow in Yahoo! Messenger allows remote attackers to execute arbitrary code via the offline mode.

Buffer overflow in Yahoo Instant Messenger 5.6.0.1351 and earlier allows remote attackers to cause a denial of service (crash) and possibly execute arbitrary code via a long filename in the download feature.

The installer in Yahoo! Messenger 4.0, 5.0 and 5.5 does not verify package signatures which could allow remote attackers to install trojan programs via DNS spoofing.

Yahoo! Messenger 4.0 sends user passwords in cleartext, which could allow remote attackers to gain privileges of other users via sniffing.