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. References: http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2017-17484 http://www.cvedetails.com/cve/CVE-2017-17484/ https://ssl.icu-project.org/trac/ticket/13490 https://ssl.icu-project.org/trac/attachment/ticket/13490/poc.cpp https://ssl.icu-project.org/trac/ticket/13510 https://ssl.icu-project.org/trac/changeset/40715 https://ssl.icu-project.org/trac/changeset/40714 https://github.com/znc/znc/issues/1459
Created icu tracking bugs for this issue: Affects: fedora-all [bug 1524820]
I think this was introduced by https://ssl.icu-project.org/trac/changeset/40455/trunk/icu4c/source/common/ucnv_u8.cpp The fixed version passes the testcase, but revision 40455 fails, then https://ssl.icu-project.org/trac/browser/trunk/icu4c/source/common/ucnv_u8.cpp?rev=39745 passes again. The poc has showed no symptoms when testing on RHEL.
Statement: This issue did not affect the versions of icu as shipped with Red Hat Enterprise Linux 5, 6, and 7.