High level conclusions

Fuzzer fuzz_desktop_entry is blocked:

The runtime code coverage of fuzz_desktop_entry covers 11.86% of its statically reachable code. This means there is some place that blocks the fuzzer to continue exploring more code at run time.

Fuzzer fuzz_mime is blocked:

The runtime code coverage of fuzz_mime covers 22.22% of its statically reachable code. This means there is some place that blocks the fuzzer to continue exploring more code at run time.

Fuzzer fuzz_menu is blocked:

The runtime code coverage of fuzz_menu covers 26.92% of its statically reachable code. This means there is some place that blocks the fuzzer to continue exploring more code at run time.

Fuzzer fuzz_icon is blocked:

The runtime code coverage of fuzz_icon covers 14.08% of its statically reachable code. This means there is some place that blocks the fuzzer to continue exploring more code at run time.

Reachability and coverage overview

Functions statically reachable by fuzzers

102 / 533

Cyclomatic complexity statically reachable by fuzzers

435 / 1962

Runtime code coverage of functions

102 / 533

The following table shows data about each function in the project. The functions included in this table correspond to all functions that exist in the executables of the fuzzers. As such, there may be functions that are from third-party libraries.

For further technical details on the meaning of columns in the below table, please see the Glossary .

Func name	Functions filename	Args	Function call depth	Reached by Fuzzers	Fuzzers runtime hit	Func lines hit %	I Count	BB Count	Cyclomatic complexity	Functions reached	Reached by functions	Accumulated cyclomatic complexity	Undiscovered complexity

Fuzzer: fuzz_icon

Call tree

The calltree shows the control flow of the fuzzer. This is overlaid with coverage information to display how much of the potential code a fuzzer can reach is in fact covered at runtime. In the following there is a link to a detailed calltree visualisation as well as a bitmap showing a high-level view of the calltree. For further information about these topics please see the glossary for full calltree and calltree overview

Call tree overview bitmap:

The distribution of callsites in terms of coloring is

Color	Runtime hitcount	Callsite count	Percentage
red	0	156	81.6%
gold	[1:9]	0	0.0%
yellow	[10:29]	0	0.0%
greenyellow	[30:49]	0	0.0%
lawngreen	50+	35	18.3%
All colors	191	100

Fuzz blockers

The following nodes represent call sites where fuzz blockers occur.

Amount of callsites blocked	Calltree index	Parent function	Callsite	Largest blocked function
108	71	xdg.IniFile.IniFile.get	call site: 00071	xdg.DesktopEntry.DesktopEntry.checkKey
19	36	...fuzz_icon.TestOneInput	call site: 00036	xdg.IconTheme.IconTheme.checkGroup
7	63	xdg.IniFile.IniFile.getList	call site: 00063	xdg.IniFile.IniFile.__getBoolean
7	183	...fuzz_icon.TestOneInput	call site: 00183	xdg.IconTheme.IconData.__init__
5	29	xdg.DesktopEntry.DesktopEntry.parse	call site: 00029	xdg.IconTheme.IconTheme.parse
4	58	xdg.IniFile.IniFile.getList	call site: 00058	re.search
3	7	xdg.IniFile.IniFile.__init__	call site: 00007	xdg.IconTheme.IconData.parse
2	26	xdg.IniFile.IniFile.parse	call site: 00026	os.path.dirname
1	3	...fuzz_icon.TestOneInput	call site: 00003	f.write

Runtime coverage analysis

Covered functions

116

Functions that are reachable but not covered

61

Reachable functions

71

Percentage of reachable functions covered

14.08%

NB: The sum of covered functions and functions that are reachable but not covered need not be equal to Reachable functions . This is because the reachability analysis is an approximation and thus at runtime some functions may be covered that are not included in the reachability analysis. This is a limitation of our static analysis capabilities.

Warning: The number of covered functions are larger than the number of reachable functions. This means that there are more functions covered at runtime than are extracted using static analysis. This is likely a result of the static analysis component failing to extract the right call graph or the coverage runtime being compiled with sanitizers in code that the static analysis has not analysed. This can happen if lto/gold is not used in all places that coverage instrumentation is used.

Function name	source code lines	source lines hit	percentage hit

Files reached

filename	functions hit
/	1
...fuzz_icon	10
xdg.IconTheme	16
xdg.IniFile	47
xdg.DesktopEntry	15

Fuzzer: fuzz_menu

Call tree

The calltree shows the control flow of the fuzzer. This is overlaid with coverage information to display how much of the potential code a fuzzer can reach is in fact covered at runtime. In the following there is a link to a detailed calltree visualisation as well as a bitmap showing a high-level view of the calltree. For further information about these topics please see the glossary for full calltree and calltree overview

Call tree overview bitmap:

The distribution of callsites in terms of coloring is

Color	Runtime hitcount	Callsite count	Percentage
red	0	166	46.7%
gold	[1:9]	0	0.0%
yellow	[10:29]	0	0.0%
greenyellow	[30:49]	0	0.0%
lawngreen	50+	189	53.2%
All colors	355	100

Fuzz blockers

The following nodes represent call sites where fuzz blockers occur.

Amount of callsites blocked	Calltree index	Parent function	Callsite	Largest blocked function
22	313	xdg.Menu.Menu.sort	call site: 00313	xdg.Menu.Menu.merge_inline
18	68	xdg.Menu._ast_const	call site: 00068	ast.NameConstant
17	240	xdg.Menu.MenuEntryCache.get_menu_entries	call site: 00240	xdg.Menu.Rule.fromFilename
14	129	xdg.Menu._to_bool	call site: 00129	xdg.Menu._to_bool
11	337	xdg.Menu.Menu.sort	call site: 00337	entry.Directory.DesktopEntry.getNoDisplay
10	56	xdg.Menu.XMLMenuBuilder.parse_rule	call site: 00056	xdg.Menu.XMLMenuBuilder.parse_rule_node
10	194	xdg.DesktopEntry.DesktopEntry.parse	call site: 00194	xdg.DesktopEntry.DesktopEntry.new
7	9	xdg.Menu.XMLMenuBuilder.parse	call site: 00009	xdg.Menu._get_menu_file_path
7	94	xdg.Menu.XMLMenuBuilder.parse_node	call site: 00094	xdg.Menu.XMLMenuBuilder.parse_merge_file
7	212	xdg.IniFile.IniFile.getList	call site: 00212	xdg.IniFile.IniFile.__getBoolean
6	223	xdg.Menu.MenuEntry.setAttributes	call site: 00223	xdg.Menu.MenuEntry.__setFilename
4	184	xdg.IconTheme.IconTheme.parse	call site: 00184	xdg.IconTheme.IconTheme.parse

Runtime coverage analysis

Covered functions

117

Functions that are reachable but not covered

133

Reachable functions

182

Percentage of reachable functions covered

26.92%

NB: The sum of covered functions and functions that are reachable but not covered need not be equal to Reachable functions . This is because the reachability analysis is an approximation and thus at runtime some functions may be covered that are not included in the reachability analysis. This is a limitation of our static analysis capabilities.

Function name	source code lines	source lines hit	percentage hit

Files reached

filename	functions hit
/	1
...fuzz_menu	7
xdg.Menu	147
xdg.DesktopEntry	11
xdg.IconTheme	6
xdg.IniFile	22

Fuzzer: fuzz_mime

Call tree

The calltree shows the control flow of the fuzzer. This is overlaid with coverage information to display how much of the potential code a fuzzer can reach is in fact covered at runtime. In the following there is a link to a detailed calltree visualisation as well as a bitmap showing a high-level view of the calltree. For further information about these topics please see the glossary for full calltree and calltree overview

Call tree overview bitmap:

The distribution of callsites in terms of coloring is

Color	Runtime hitcount	Callsite count	Percentage
red	0	64	49.6%
gold	[1:9]	0	0.0%
yellow	[10:29]	0	0.0%
greenyellow	[30:49]	0	0.0%
lawngreen	50+	65	50.3%
All colors	129	100

Fuzz blockers

The following nodes represent call sites where fuzz blockers occur.

Amount of callsites blocked	Calltree index	Parent function	Callsite	Largest blocked function
35	45	xdg.Mime.MagicDB.merge_file	call site: 00045	xdg.Mime.MagicMatchAny.from_file
7	94	xdg.Mime.get_type2	call site: 00094	xdg.Mime._get_type_by_stat
6	31	xdg.Mime.GlobDB.finalise	call site: 00031	mtype.canonical
3	90	xdg.Mime.get_type2	call site: 00090	xdg.Mime.get_type_by_name
2	13	xdg.BaseDirectory.load_data_paths	call site: 00013	.open
2	82	xdg.Mime.MagicDB.finalise	call site: 00082	rule.maxlen
2	86	xdg.Mime._cache_database	call site: 00086	.open
2	126	...fuzz_mime.TestOneInput	call site: 00126	.str
1	19	xdg.Mime._cache_database	call site: 00019	xdg.Mime.GlobDB.merge_file
1	41	xdg.Mime._cache_database	call site: 00041	xdg.Mime.MagicDB.merge_file
1	103	xdg.Mime.get_type2	call site: 00103	.len
1	111	xdg.Mime._is_text	call site: 00111	.any

Runtime coverage analysis

Covered functions

116

Functions that are reachable but not covered

56

Reachable functions

72

Percentage of reachable functions covered

22.22%

NB: The sum of covered functions and functions that are reachable but not covered need not be equal to Reachable functions . This is because the reachability analysis is an approximation and thus at runtime some functions may be covered that are not included in the reachability analysis. This is a limitation of our static analysis capabilities.

Warning: The number of covered functions are larger than the number of reachable functions. This means that there are more functions covered at runtime than are extracted using static analysis. This is likely a result of the static analysis component failing to extract the right call graph or the coverage runtime being compiled with sanitizers in code that the static analysis has not analysed. This can happen if lto/gold is not used in all places that coverage instrumentation is used.

Function name	source code lines	source lines hit	percentage hit

Files reached

filename	functions hit
/	1
...fuzz_mime	14
xdg.Mime	63
xdg.BaseDirectory	2

Fuzzer: fuzz_desktop_entry

Call tree

The calltree shows the control flow of the fuzzer. This is overlaid with coverage information to display how much of the potential code a fuzzer can reach is in fact covered at runtime. In the following there is a link to a detailed calltree visualisation as well as a bitmap showing a high-level view of the calltree. For further information about these topics please see the glossary for full calltree and calltree overview

Call tree overview bitmap:

The distribution of callsites in terms of coloring is

Color	Runtime hitcount	Callsite count	Percentage
red	0	109	75.1%
gold	[1:9]	0	0.0%
yellow	[10:29]	0	0.0%
greenyellow	[30:49]	0	0.0%
lawngreen	50+	36	24.8%
All colors	145	100

Fuzz blockers

The following nodes represent call sites where fuzz blockers occur.

Amount of callsites blocked	Calltree index	Parent function	Callsite	Largest blocked function
82	61	...fuzz_desktop_entry.TestOneInput	call site: 00061	xdg.IniFile.IniFile.checkValue
10	31	xdg.DesktopEntry.DesktopEntry.parse	call site: 00031	xdg.DesktopEntry.DesktopEntry.new
7	49	xdg.IniFile.IniFile.getList	call site: 00049	xdg.IniFile.IniFile.__getBoolean
4	44	xdg.IniFile.IniFile.getList	call site: 00044	re.search
3	11	xdg.IconTheme.IconTheme.parse	call site: 00011	xdg.IconTheme.IconTheme.parse
2	26	xdg.IconTheme.IconTheme.parse	call site: 00026	os.path.dirname
1	23	xdg.IniFile.IniFile.parse	call site: 00023	xdg.DesktopEntry.DesktopEntry.parse

Runtime coverage analysis

Covered functions

117

Functions that are reachable but not covered

52

Reachable functions

59

Percentage of reachable functions covered

11.86%

NB: The sum of covered functions and functions that are reachable but not covered need not be equal to Reachable functions . This is because the reachability analysis is an approximation and thus at runtime some functions may be covered that are not included in the reachability analysis. This is a limitation of our static analysis capabilities.

Warning: The number of covered functions are larger than the number of reachable functions. This means that there are more functions covered at runtime than are extracted using static analysis. This is likely a result of the static analysis component failing to extract the right call graph or the coverage runtime being compiled with sanitizers in code that the static analysis has not analysed. This can happen if lto/gold is not used in all places that coverage instrumentation is used.

Function name	source code lines	source lines hit	percentage hit

Files reached

filename	functions hit
/	1
...fuzz_desktop_entry	9
xdg.DesktopEntry	20
xdg.IconTheme	6
xdg.IniFile	31

Optimal target analysis

Remaining optimal interesting functions

The following table shows a list of functions that are optimal targets. Optimal targets are identified by finding the functions that in combination, yield a high code coverage.

Func name	Functions filename	Arg count	Args	Function depth	hitcount	instr count	bb count	cyclomatic complexity	Reachable functions	Incoming references	total cyclomatic complexity	Unreached complexity
lxml.doctestcompare.LXMLOutputChecker.output_difference	lxml.doctestcompare	4	['N/A', 'N/A', 'N/A', 'N/A']	2	0	3	3	4	48	0	163	145
lxml.html._MethodFunc.__call__	lxml.html	4	['N/A', 'N/A', 'N/A', 'N/A']	2	0	0	5	5	29	0	103	97
lxml.html.HtmlMixin.rewrite_links	lxml.html	4	['N/A', 'N/A', 'N/A', 'N/A']	3	0	4	7	6	25	3	93	77
xdg.MenuEditor.MenuEditor.__addEntry	xdg.MenuEditor	5	['N/A', 'N/A', 'N/A', 'N/A', 'N/A']	2	0	8	6	5	24	7	83	74
xdg.IconTheme.getIconPath	xdg.IconTheme	4	['N/A', 'N/A', 'N/A', 'N/A']	5	0	1	11	7	53	1	191	67
lxml.ElementInclude.include	lxml.ElementInclude	4	['N/A', 'N/A', 'N/A', 'N/A']	1	0	1	6	5	23	0	81	66
lxml.html.soupparser._parse	lxml.html.soupparser	4	['N/A', 'N/A', 'N/A', 'N/A']	2	0	0	6	5	23	3	78	63
lxml.html.formfill._fill_form	lxml.html.formfill	2	['N/A', 'N/A']	2	0	2	7	6	18	2	66	47
lxml.html._diffcommand.main	lxml.html._diffcommand	1	['N/A']	1	0	5	5	5	19	0	64	46
xdg.MenuEditor.MenuEditor.__saveEntries	xdg.MenuEditor	2	['N/A', 'N/A']	2	0	3	4	5	16	2	59	44

Implementing fuzzers that target the above functions will improve reachability such that it becomes:

Functions statically reachable by fuzzers

173 / 533

Cyclomatic complexity statically reachable by fuzzers

740 / 1962

All functions overview

If you implement fuzzers for these functions, the status of all functions in the project will be:

Func name	Functions filename	Args	Function call depth	Reached by Fuzzers	Fuzzers runtime hit	Func lines hit %	I Count	BB Count	Cyclomatic complexity	Functions reached	Reached by functions	Accumulated cyclomatic complexity	Undiscovered complexity

This section shows analysis of runtime coverage data.

For futher technical details on how this section is generated, please see the Glossary .

Complex functions with low coverage

Func name	Function total lines	Lines covered at runtime	percentage covered	Reached by fuzzers
xdg.IconTheme.IconTheme.checkKey	45	1	2.222%	['fuzz_icon']
xdg.IconTheme.getIconPath	41	0	0.0%	[]
xdg.IniFile.IniFile.get	38	17	44.73%	['fuzz_icon', 'fuzz_menu', 'fuzz_desktop_entry']
xdg.DesktopEntry.DesktopEntry.checkKey	137	0	0.0%	['fuzz_icon', 'fuzz_desktop_entry']
xdg.Locale._expand_lang	32	0	0.0%	[]
xdg.Menu.Menu.sort	82	41	50.0%	['fuzz_menu']
menu.MenuEntries.append	46	24	52.17%	['fuzz_menu']
xdg.Mime.get_type2	31	13	41.93%	['fuzz_mime']

This section shows which files and directories are considered in this report. The main reason for showing this is fuzz introspector may include more code in the reasoning than is desired. This section helps identify if too many files/directories are included, e.g. third party code, which may be irrelevant for the threat model. In the event too much is included, fuzz introspector supports a configuration file that can exclude data from the report. See the following link for more information on how to create a config file: link

Files in report

Source file	Reached by	Covered by
	[]	[]
xdg	[]	[]
urllib2	[]	[]
lxml.html.diff	[]	[]
lxml.html.defs	[]	[]
lxml.includes	[]	[]
lxml.html.html5parser	[]	[]
xdg.DesktopEntry	['fuzz_icon', 'fuzz_menu', 'fuzz_desktop_entry']	[]
lxml.builder	[]	[]
lxml.usedoctest	[]	[]
lxml.html.ElementSoup	[]	[]
io	[]	[]
lxml.sax	[]	[]
lxml.html.usedoctest	[]	[]
lxml.html.formfill	[]	[]
doctest	[]	[]
...fuzz_desktop_entry	['fuzz_desktop_entry']	[]
re	[]	[]
html	[]	[]
...fuzz_menu	['fuzz_menu']	[]
cssselect	[]	[]
lxml.cssselect	[]	[]
warnings	[]	[]
lxml.html.clean	[]	[]
atheris	[]	[]
lxml.html._diffcommand	[]	[]
locale	[]	[]
xdg.Locale	[]	[]
shutil	[]	[]
lxml.isoschematron	[]	[]
lxml.html._html5builder	[]	[]
urllib	[]	[]
...fuzz_mime	['fuzz_mime']	[]
cgi	[]	[]
lxml.etree	[]	[]
tempfile	[]	[]
lxml._elementpath	[]	[]
xdg.RecentFiles	[]	[]
optparse	[]	[]
lxml.html	[]	[]
xdg.Mime	['fuzz_mime']	[]
webbrowser	[]	[]
lxml.pyclasslookup	[]	[]
lxml.ElementInclude	[]	[]
...fuzz_icon	['fuzz_icon']	[]
os	[]	[]
lxml.html.builder	[]	[]
xdg.Menu	['fuzz_menu']	[]
bs4	[]	[]
xdg.util	[]	[]
xdg.Exceptions	[]	[]
urlparse	[]	[]
fcntl	[]	[]
getpass	[]	[]
imp	[]	[]
pkg_resources	[]	[]
lxml.doctestcompare	[]	[]
html5lib	[]	[]
xdg.BaseDirectory	['fuzz_mime']	[]
xdg.Config	[]	[]
xdg.IniFile	['fuzz_icon', 'fuzz_menu', 'fuzz_desktop_entry']	[]
lxml	[]	[]
fnmatch	[]	[]
subprocess	[]	[]
xml	[]	[]
time	[]	[]
lxml.html.soupparser	[]	[]
xdg.MenuEditor	[]	[]
stat	[]	[]
collections	[]	[]
BeautifulSoup	[]	[]
ast	[]	[]
lxml.objectify	[]	[]
	[]	[]
xdg.IconTheme	['fuzz_icon', 'fuzz_menu', 'fuzz_desktop_entry']	[]
functools	[]	[]
lxml.html._setmixin	[]	[]
sys	[]	[]

Directories in report

Directory