unicode loads unicode data downloaded from unicode.org into nodejs. Unicode before 9.0.0 downloads binary resources over HTTP, which leaves it vulnerable to MITM attacks.

The ucnv_UTF8FromUTF8 function in ucnv_u8.cpp in International Components for Unicode (ICU) for C/C++ through 60.1 mishandles ucnv_convertEx calls for UTF-8 to UTF-8 conversion, which allows remote attackers to cause a denial of service (stack-based buffer overflow and application crash) or possibly have unspecified other impact via a crafted string, as demonstrated by ZNC.

Double free in i18n/zonemeta.cpp in International Components for Unicode (ICU) for C/C++ through 59.1 allows remote attackers to execute arbitrary code via a crafted string, aka a "redundant UVector entry clean up function call" issue.

The Regular Expressions package in International Components for Unicode (ICU) for C/C++ before 2014-12-03, as used in Google Chrome before 40.0.2214.91, calculates certain values without ensuring that they can be represented in a 24-bit field, which allows remote attackers to cause a denial of service (memory corruption) or possibly have unspecified other impact via a crafted string, a related issue to CVE-2014-7923.

International Components for Unicode (ICU) for C/C++ before 2017-02-13 has an out-of-bounds write caused by a heap-based buffer overflow related to the utf8TextAccess function in common/utext.cpp and the utext_setNativeIndex* function.

International Components for Unicode (ICU) for C/C++ before 2017-02-13 has an out-of-bounds write caused by a heap-based buffer overflow related to the utf8TextAccess function in common/utext.cpp and the utext_moveIndex32* function.

Stack-based buffer overflow in the ures_getByKeyWithFallback function in common/uresbund.cpp in International Components for Unicode (ICU) before 54.1 for C/C++ allows remote attackers to cause a denial of service or possibly have unspecified other impact via a crafted uloc_getDisplayName call.

Stack-based buffer overflow in the Locale class in common/locid.cpp in International Components for Unicode (ICU) through 57.1 for C/C++ allows remote attackers to cause a denial of service (application crash) or possibly have unspecified other impact via a long locale string.

The uloc_acceptLanguageFromHTTP function in common/uloc.cpp in International Components for Unicode (ICU) through 57.1 for C/C++ does not ensure that there is a '\0' character at the end of a certain temporary array, which allows remote attackers to cause a denial of service (out-of-bounds read) or possibly have unspecified other impact via a call with a long httpAcceptLanguage argument.

Unspecified vulnerability in International Components for Unicode (ICU) before 53.1.0, as used in Apple OS X before 10.11 and watchOS before 2, has unknown impact and attack vectors.