CVE-2021-27219

A flaw was found in Glib's content type parsing logic. This buffer underflow vulnerability occurs because the length of a header line is stored in a signed integer, which can lead to integer wraparound for very large inputs. This results in pointer underflow and out-of-bounds memory access. Exploitation requires a local user to install or process a specially crafted treemagic file, which can lead to local denial of service or application instability.

An issue was discovered in GNOME GLib before 2.78.5, and 2.79.x and 2.80.x before 2.80.1, where a GDBus-based client subscribing to signals from a trusted system service on a shared computer can receive spoofed D-Bus signals from other users of the same computer.

In GNOME GLib before 2.82.1, the file gio/gsocks4aproxy.c has an off-by-one error leading to a buffer overflow because SOCKS4_CONN_MSG_LEN is insufficient for a trailing null character.

Denial of Service and resource exhaustion vulnerability in the GDBus component of GLib. The gdbusauth authentication mechanism fails to enforce proper length limitations on data lines read from a client. An unauthenticated attacker can send excessively long data streams, causing massive memory and CPU consumption, potentially leading to a crash or system hang.

A flaw in GLib's g_dbus_node_info_new_for_xml() function when processing malformed D-Bus introspection XML can cause an unsigned integer overflow and out-of-bounds read, leading to denial of service.

In GLib, the D-Bus client-side implementation of the DBUS_COOKIE_SHA1 SASL authentication mechanism does not validate the cookie_context parameter received from the server. A malicious D-Bus server can supply a cookie_context containing path traversal sequences, causing the client to read an arbitrary file and exfiltrate sensitive data.

An off-by-one error was found in GLib's g_key_file_get_locale_string_list function in gkeyfile.c when loading a key file with an empty value. This flaw can cause an out-of-bounds access of 1 byte or a denial of service when the out-of-bounds access crosses a page boundary.

A flaw was found in GLib where a buffer over-read occurs in g_io_channel_read_line_backend() in giochannel.c when a custom line terminator longer than one byte is set, causing memcmp to read past the GString buffer. This vulnerability can lead to minor information disclosure of 7 bytes or denial of service if the over-read crosses a page boundary.

A flaw was found in GLib where a buffer over-read occurs in the g_regex_replace function when using the G_REGEX_RAW compile flag and case-change replacement escapes. The string_append function processes matched substrings using UTF-8 functions that assume valid UTF-8 input, even when the string is treated as raw bytes. This can lead to minor information disclosure of 1-5 bytes and a denial of service when the buffer over-read crosses a page boundary.

A flaw was found in GLib where an out-of-bounds read of 2 bytes occurs in the g_date_time_get_ymd function in glib/gdatetime.c when processing an invalid GDateTime object created by g_date_time_add_full. This can corrupt date output and cause logic errors.