Use-after-free vulnerability in the create_smp_dialog function in gtk-dialog.c in the Off-the-Record Messaging (OTR) pidgin-otr plugin before 4.0.2 for Pidgin allows remote attackers to execute arbitrary code via vectors related to the "Authenticate buddy" menu item.

Absolute path traversal vulnerability in the untar_block function in win32/untar.c in Pidgin before 2.10.10 on Windows allows remote attackers to write to arbitrary files via a drive name in a tar archive of a smiley theme.

The jabber_idn_validate function in jutil.c in the Jabber protocol plugin in libpurple in Pidgin before 2.10.10 allows remote attackers to obtain sensitive information from process memory via a crafted XMPP message.

The (1) bundled GnuTLS SSL/TLS plugin and the (2) bundled OpenSSL SSL/TLS plugin in libpurple in Pidgin before 2.10.10 do not properly consider the Basic Constraints extension during verification of X.509 certificates from SSL servers, which allows man-in-the-middle attackers to spoof servers and obtain sensitive information via a crafted certificate.

markup.c in the MXit protocol plugin in libpurple in Pidgin before 2.10.10 allows remote servers to cause a denial of service (application crash) via a large length value in an emoticon response.

nmevent.c in the Novell GroupWise protocol plugin in libpurple in Pidgin before 2.10.10 allows remote servers to cause a denial of service (application crash) via a crafted server message that triggers a large memory allocation.

Pidgin before 2.10.8 allows remote MSN servers to cause a denial of service (NULL pointer dereference and crash) via a crafted (1) SOAP response, (2) OIM XML response, or (3) Content-Length header.

libpurple/protocols/yahoo/libymsg.c in Pidgin before 2.10.8 allows remote attackers to cause a denial of service (crash) via a Yahoo! P2P message with a crafted length field, which triggers a buffer over-read.

Integer overflow in libpurple/protocols/gg/lib/http.c in the Gadu-Gadu (gg) parser in Pidgin before 2.10.8 allows remote attackers to have an unspecified impact via a large Content-Length value, which triggers a buffer overflow.

Integer signedness error in the MXit functionality in Pidgin before 2.10.8 allows remote attackers to cause a denial of service (segmentation fault) via a crafted emoticon value, which triggers an integer overflow and a buffer overflow.