From ba245013f2801b102fdaa305fbc1bbf8b04866f8 Mon Sep 17 00:00:00 2001 From: Julian Andres Klode Date: Fri, 18 Jan 2019 09:13:52 +0100 Subject: SECURITY UPDATE: content injection in http method (CVE-2019-3462) This fixes a security issue that can be exploited to inject arbritrary debs or other files into a signed repository as followed: (1) Server sends a redirect to somewhere%0a (where %0a is \n encoded) (2) apt method decodes the redirect (because the method encodes the URLs before sending them out), writting something like somewhere\n into its output (3) apt then uses the headers injected for validation purposes. Regression-Of: c34ea12ad509cb34c954ed574a301c3cbede55ec LP: #1812353 --- apt-pkg/acquire-method.cc | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'apt-pkg/acquire-method.cc') diff --git a/apt-pkg/acquire-method.cc b/apt-pkg/acquire-method.cc index ab0908014..bd947209b 100644 --- a/apt-pkg/acquire-method.cc +++ b/apt-pkg/acquire-method.cc @@ -458,6 +458,12 @@ void pkgAcqMethod::Status(const char *Format,...) * the worker will enqueue again later on to the right queue */ void pkgAcqMethod::Redirect(const string &NewURI) { + if (NewURI.find_first_not_of(" !\"#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\\]^_`abcdefghijklmnopqrstuvwxyz{|}~") != std::string::npos) + { + _error->Error("SECURITY: URL redirect target contains control characters, rejecting."); + Fail(); + return; + } std::cout << "103 Redirect\nURI: " << Queue->Uri << "\n" << "New-URI: " << NewURI << "\n" << "\n" << std::flush; -- cgit v1.2.3