Penetration Test Report (SECConsult): Mailvelope Extensions pdf

Mailvelope Extensions
Security Audit
Authors: W. Ettlinger, A. Mynzhasova
SEC Consult Deutschland Unternehmensberatung GmbH
Ullsteinstraße 130, Turm B/8. floor
12109 Berlin, Deutschland
www.sec-consult.com
Federal Office for Information Security
Post Box 20 03 63
D-53133 Bonn
Phone: +49 22899 9582-0
E-Mail: bsi@bsi.bund.de
Internet: https://www.bsi.bund.de
© Federal Office for Information Security 2019
Table of Contents
Table of Contents
1 Management Summary...................................................................................................................................................................5
1.1 Scope and Timetable..................................................................................................................................................................5
1.2 Results...............................................................................................................................................................................................6
1.2.1 Worst Case Scenarios..........................................................................................................................................................6
1.3 Suggested Measures...................................................................................................................................................................7
1.3.1 Measures with Immediate Need for Action...............................................................................................................7
1.3.2 Further Measures...................................................................................................................................................................7
1.4 Disclaimer.........................................................................................................................................................................................7
2 Approach................................................................................................................................................................................................8
2.1 Testing Method..............................................................................................................................................................................8
2.1.1 Scope Limitations...................................................................................................................................................................8
2.1.2 Tested Vulnerabilities...........................................................................................................................................................8
2.2 Test Setup........................................................................................................................................................................................9
2.2.1 OpenPGP.js...............................................................................................................................................................................9
2.2.2 Mailvelope.................................................................................................................................................................................9
2.3 Risk Calculation...........................................................................................................................................................................10
2.3.1 Definition of the Term Likelihood................................................................................................................................10
2.3.2 Definition of the Term Severity....................................................................................................................................11
2.4 Total Risk.......................................................................................................................................................................................11
3 Vulnerability Summary................................................................................................................................................................12
3.1 Total Risk Per System..............................................................................................................................................................12
3.2 Risk of Each Vulnerability.......................................................................................................................................................12
4 Detailed Analysis..............................................................................................................................................................................14
4.1 Mailvelope......................................................................................................................................................................................14
4.1.1 General Information...........................................................................................................................................................14
4.1.2 Clickjacking (CVE-2019-9147).......................................................................................................................................14
4.1.3 Insufficient Key Equality Check....................................................................................................................................16
4.1.4 Private Key Operations Require no User Interaction (CVE-2019-9149)....................................................18
4.1.5 [Expunged Finding]............................................................................................................................................................20
4.1.6 Password Entry Indicator Bypass................................................................................................................................21
4.1.7 Secondary User Ids Not Visible during Key Import.............................................................................................22
4.1.8 Key Import User Interaction Bypass (CVE-2019-9150)....................................................................................26
4.1.9 Low Distinguishability of Secure Backgrounds......................................................................................................29
4.1.10 Cross-Site Scripting............................................................................................................................................................31
4.1.11 Missing Message and Key Validity Checks (CVE-2019-9148).........................................................................35
4.1.12 Note: Alteration of the GnuPG Trust Model............................................................................................................39
4.1.13 Note: Side Channel Attacks............................................................................................................................................39
4.1.14 Note: Outdated Software................................................................................................................................................44
4.1.15 Notes.........................................................................................................................................................................................45
4.2 OpenPGP.js...................................................................................................................................................................................48
4.2.1 General Information...........................................................................................................................................................48
4.2.2 Invalid Curve Attack (CVE-2019-9155)...............................................................................................................