https://github.com/python/cpython/commit/51332c467ed2e07a191f903d554d0c54248... commit: 51332c467ed2e07a191f903d554d0c54248e4d88 branch: 3.6 author: Steve Dower <steve.dower@python.org> committer: GitHub <noreply@github.com> date: 2020-01-30T21:12:20-05:00 summary: [3.6] bpo-39401: Avoid unsafe DLL load on Windows 7 and earlier (GH-18231) (GH-18233) files: A Misc/NEWS.d/next/Security/2020-01-28-20-54-09.bpo-39401.he7h_A.rst M PC/getpathp.c M Tools/msi/bundle/bootstrap/PythonBootstrapperApplication.cpp diff --git a/Misc/NEWS.d/next/Security/2020-01-28-20-54-09.bpo-39401.he7h_A.rst b/Misc/NEWS.d/next/Security/2020-01-28-20-54-09.bpo-39401.he7h_A.rst new file mode 100644 index 0000000000000..5071e126b70d0 --- /dev/null +++ b/Misc/NEWS.d/next/Security/2020-01-28-20-54-09.bpo-39401.he7h_A.rst @@ -0,0 +1 @@ +Avoid unsafe load of ``api-ms-win-core-path-l1-1-0.dll`` at startup on Windows 7. diff --git a/PC/getpathp.c b/PC/getpathp.c index 880ea7b966e5c..e86c376fb4d34 100644 --- a/PC/getpathp.c +++ b/PC/getpathp.c @@ -224,7 +224,8 @@ static void join(wchar_t *buffer, const wchar_t *stuff) { if (_PathCchCombineEx_Initialized == 0) { - HMODULE pathapi = LoadLibraryW(L"api-ms-win-core-path-l1-1-0.dll"); + HMODULE pathapi = LoadLibraryExW(L"api-ms-win-core-path-l1-1-0.dll", NULL, + LOAD_LIBRARY_SEARCH_SYSTEM32); if (pathapi) _PathCchCombineEx = (PPathCchCombineEx)GetProcAddress(pathapi, "PathCchCombineEx"); else @@ -249,7 +250,8 @@ static PPathCchCanonicalizeEx _PathCchCanonicalizeEx; static void canonicalize(wchar_t *buffer, const wchar_t *path) { if (_PathCchCanonicalizeEx_Initialized == 0) { - HMODULE pathapi = LoadLibraryW(L"api-ms-win-core-path-l1-1-0.dll"); + HMODULE pathapi = LoadLibraryExW(L"api-ms-win-core-path-l1-1-0.dll", NULL, + LOAD_LIBRARY_SEARCH_SYSTEM32); if (pathapi) { _PathCchCanonicalizeEx = (PPathCchCanonicalizeEx)GetProcAddress(pathapi, "PathCchCanonicalizeEx"); } diff --git a/Tools/msi/bundle/bootstrap/PythonBootstrapperApplication.cpp b/Tools/msi/bundle/bootstrap/PythonBootstrapperApplication.cpp index e88981fc3abb4..d14aeff190470 100644 --- a/Tools/msi/bundle/bootstrap/PythonBootstrapperApplication.cpp +++ b/Tools/msi/bundle/bootstrap/PythonBootstrapperApplication.cpp @@ -3042,8 +3042,16 @@ class PythonBootstrapperApplication : public CBalBaseBootstrapperApplication { } } else { if (IsWindows7SP1OrGreater()) { - BalLog(BOOTSTRAPPER_LOG_LEVEL_STANDARD, "Target OS is Windows 7 SP1 or later"); - return; + HMODULE hKernel32 = GetModuleHandleW(L"kernel32"); + if (hKernel32 && !GetProcAddress(hKernel32, "AddDllDirectory")) { + BalLog(BOOTSTRAPPER_LOG_LEVEL_ERROR, "Detected Windows 7 SP1 without KB2533623"); + BalLog(BOOTSTRAPPER_LOG_LEVEL_ERROR, "KB2533623 update is required to continue."); + /* The "MissingSP1" error also specifies updates are required */ + LocGetString(_wixLoc, L"#(loc.FailureWin7MissingSP1)", &pLocString); + } else { + BalLog(BOOTSTRAPPER_LOG_LEVEL_STANDARD, "Target OS is Windows 7 SP1 or later"); + return; + } } else if (IsWindows7OrGreater()) { BalLog(BOOTSTRAPPER_LOG_LEVEL_ERROR, "Detected Windows 7 RTM"); BalLog(BOOTSTRAPPER_LOG_LEVEL_ERROR, "Service Pack 1 is required to continue installation");