A flaw was found in libebml before 1.4.2. A heap overflow bug exists in the implementation of EbmlString::ReadData and EbmlUnicodeString::ReadData in libebml.
The EbmlElement::ReadCodedSizeValue function in libEBML before 1.3.3 allows context-dependent attackers to obtain sensitive information from process heap memory via a crafted length value in an EBML id, which triggers an invalid memory access.
The EbmlUnicodeString::UpdateFromUTF8 function in libEBML before 1.3.3 allows context-dependent attackers to obtain sensitive information from process heap memory via a crafted UTF-8 string, which triggers an invalid memory access.
Use-after-free vulnerability in the EbmlMaster::Read function in libEBML before 1.3.3 allows context-dependent attackers to have unspecified impact via a "deeply nested element with infinite size" followed by another element of an upper level in an EBML document.