Fuzz introspector
For issues and ideas: https://github.com/ossf/fuzz-introspector/issues
Project coverage
Per-fuzzer coverage

Table of contents

Project overview: pupnp
High level conclusions
Reachability and coverage overview
Fuzzers overview
Project functions overview
Fuzzer details
Fuzzer: FuzzIxml
Call tree
Fuzz blockers
Runtime coverage analysis
Files reached
Fuzzer: FuzzHttp
Call tree
Fuzz blockers
Runtime coverage analysis
Files reached
Analyses and suggestions
Optimal target analysis
Remaining optimal interesting functions
All functions overview
Fuzz engine guidance
fuzzer/FuzzIxml.c
Dictionary
Fuzzer function priority
fuzzer/FuzzHttp.c
Dictionary
Fuzzer function priority
Runtime coverage analysis
Complex functions with low coverage
Files and Directories in report
Files in report
Directories in report
Metadata section
Report generation date: 2026-07-16

Project overview: pupnp

High level conclusions

Reachability and coverage overview

Functions statically reachable by fuzzers
17.0%
180 / 1076
Cyclomatic complexity statically reachable by fuzzers
22.0%
1209 / 5509
Runtime code coverage of functions
16.0%
174 / 1076

Fuzzers overview

Fuzzer Fuzzer filename Functions Reached Functions unreached Fuzzer depth Files reached Basic blocks reached Cyclomatic complexity Details
FuzzIxml fuzzer/FuzzIxml.c 125 94 12 9 1792 754 FuzzIxml.c
FuzzHttp fuzzer/FuzzHttp.c 106 1079 11 8 1323 562 FuzzHttp.c

Project functions overview

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 Runtime reached by Fuzzers Combined 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 details

Fuzzer: FuzzIxml

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

Full calltree

Call tree overview bitmap:

The distribution of callsites in terms of coloring is
Color Runtime hitcount Callsite count Percentage
red 0 67 15.8%
gold [1:9] 3 0.70%
yellow [10:29] 0 0.0%
greenyellow [30:49] 4 0.94%
lawngreen 50+ 350 82.5%
All colors 424 100

Fuzz blockers

The following nodes represent call sites where fuzz blockers occur.

Amount of callsites blocked Calltree index Parent function Callsite Largest blocked function
22 398 ixmlPrintDomTreeRecursive call site: 00398 ixmlPrintDomTreeRecursive
7 375 ixmlPrintDomTreeRecursive call site: 00375 copy_with_escape
5 346 ixmlPrintDomTree call site: 00346 copy_with_escape
4 275 ixmlNode_isParent call site: 00275 ixmlNode_removeChild
2 16 Parser_readFileOrBuffer call site: 00016 fclose
2 248 ixmlDocument_createElementEx call site: 00248 ixmlElement_free
2 297 ixmlDocument_createCDATASectionEx call site: 00297 ixmlCDATASection_free
2 309 ixmlDocument_createAttributeEx call site: 00309 ixmlAttr_free
2 358 copy_with_escape call site: 00358 ixml_membuf_append_str
1 21 Parser_readFileOrBuffer call site: 00021 safe_strdup
1 23 safe_strdup call site: 00023 strdup
1 25 safe_strdup call site: 00025 Parser_free

Runtime coverage analysis

Covered functions
99
Functions that are reachable but not covered
26
Reachable functions
125
Percentage of reachable functions covered
79.2%
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
fuzzer/FuzzIxml.c 2
ixml/src/ixml.c 7
ixml/src/ixmlparser.c 52
ixml/src/ixmlmembuf.c 8
ixml/src/node.c 18
ixml/src/document.c 7
ixml/src/ixmldebug.c 1
ixml/src/element.c 6
ixml/src/attr.c 2

Fuzzer: FuzzHttp

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

Full calltree

Call tree overview bitmap:

The distribution of callsites in terms of coloring is
Color Runtime hitcount Callsite count Percentage
red 0 28 11.6%
gold [1:9] 4 1.65%
yellow [10:29] 4 1.65%
greenyellow [30:49] 2 0.82%
lawngreen 50+ 203 84.2%
All colors 241 100

Fuzz blockers

The following nodes represent call sites where fuzz blockers occur.

Amount of callsites blocked Calltree index Parent function Callsite Largest blocked function
14 120 parser_parse_chunky_entity call site: 00120 UpnpDisplayFileAndLine
2 75 match_non_ws_string call site: 00075 parse_uri
2 112 vfmatch call site: 00112 __assert_fail
2 170 parser_parse_headers call site: 00170 membuffer_destroy
2 180 FreeListAlloc call site: 00180 membuffer_destroy
1 33 membuffer_set_size call site: 00033 realloc
1 108 read_until_crlf call site: 00108 match_char
1 110 match_char call site: 00110 scanner_get_token
1 167 membuffer_assign call site: 00167 membuffer_destroy
1 202 raw_to_int call site: 00202 __assert_fail
1 225 parser_parse_responseline call site: 00225 __assert_fail

Runtime coverage analysis

Covered functions
77
Functions that are reachable but not covered
29
Reachable functions
106
Percentage of reachable functions covered
72.64%
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
fuzzer/FuzzHttp.c 1
upnp/src/genlib/net/http/httpparser.c 39
upnp/src/threadutil/LinkedList.c 10
upnp/src/threadutil/FreeList.c 4
upnp/src/genlib/util/membuffer.c 12
upnp/src/genlib/net/uri/uri.c 9
upnp/src/api/upnpdebug.c 3
upnp/src/genlib/util/strintmap.c 1

Analyses and suggestions

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
UpnpInit2 /src/pupnp/upnp/src/api/upnpapi.c 2 ['N/A', 'short'] 18 0 103 20 9 673 0 3565 2298
UpnpSendActionExAsync /src/pupnp/upnp/src/api/upnpapi.c 8 ['int', 'N/A', 'N/A', 'N/A', 'N/A', 'N/A', 'N/A', 'N/A'] 15 0 262 35 14 407 0 2159 254
UpnpRegisterRootDevice2 /src/pupnp/upnp/src/api/upnpapi.c 7 ['int', 'N/A', 'size_t', 'int', 'N/A', 'N/A', 'N/A'] 16 0 261 25 11 320 0 1962 233
UpnpNotify /src/pupnp/upnp/src/api/upnpapi.c 6 ['int', 'N/A', 'N/A', 'N/A', 'N/A', 'int'] 16 0 122 20 7 225 0 1166 110
ixmlDocument_importNode /src/pupnp/ixml/src/document.c 4 ['N/A', 'N/A', 'int', 'N/A'] 9 0 77 13 6 38 0 170 87
UpnpOpenHttpGetProxy /src/pupnp/upnp/src/api/upnpapi.c 7 ['N/A', 'N/A', 'N/A', 'N/A', 'N/A', 'N/A', 'int'] 11 0 87 12 5 150 0 819 74
UpnpSearchAsync /src/pupnp/upnp/src/api/upnpapi.c 4 ['int', 'int', 'N/A', 'N/A'] 7 0 95 16 5 56 0 233 54
ixmlElement_setAttributeNS /src/pupnp/ixml/src/element.c 4 ['N/A', 'N/A', 'N/A', 'N/A'] 5 0 267 44 19 26 0 144 47
UpnpActionRequest_dup /src/pupnp/upnp/src/api/UpnpActionRequest.c 1 ['N/A'] 4 0 35 6 3 30 0 79 47
UpnpStateVarRequest_dup /src/pupnp/upnp/src/api/UpnpStateVarRequest.c 1 ['N/A'] 4 0 35 6 3 26 0 71 37

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

Functions statically reachable by fuzzers
68.0%
729 / 1076
Cyclomatic complexity statically reachable by fuzzers
78.0%
4302 / 5509

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 Runtime reached by Fuzzers Combined 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

Fuzz engine guidance

This sections provides heuristics that can be used as input to a fuzz engine when running a given fuzz target. The current focus is on providing input that is usable by libFuzzer.

fuzzer/FuzzIxml.c

Dictionary

Use this with the libFuzzer -dict=DICT.file flag


Fuzzer function priority

Use one of these functions as input to libfuzzer with flag: -focus_function name 

-focus_function=['ixmlPrintDomTreeRecursive', 'ixmlPrintDomTree', 'ixmlNode_isParent', 'Parser_readFileOrBuffer', 'ixmlDocument_createElementEx', 'ixmlDocument_createCDATASectionEx', 'ixmlDocument_createAttributeEx', 'copy_with_escape']

fuzzer/FuzzHttp.c

Dictionary

Use this with the libFuzzer -dict=DICT.file flag


Fuzzer function priority

Use one of these functions as input to libfuzzer with flag: -focus_function name 

-focus_function=['parser_parse_chunky_entity', 'match_non_ws_string', 'vfmatch', 'parser_parse_headers', 'FreeListAlloc', 'membuffer_set_size', 'read_until_crlf', 'match_char', 'membuffer_assign', 'raw_to_int']

Runtime coverage analysis

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
ixmlDocument_createElementEx 34 17 50.0% ['FuzzIxml']
ixmlDocument_createCDATASectionEx 33 17 51.51% ['FuzzIxml']
ixmlElement_setAttributeNode_common 69 34 49.27% ['FuzzIxml']
ixmlPrintDomTree 48 13 27.08% ['FuzzIxml']
ixmlNode_setNodeProperties 35 13 37.14% ['FuzzIxml']

Files and Directories in report

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
[] []
/src/pupnp/ixml/src/ixmlmembuf.c ['FuzzIxml'] ['FuzzIxml']
/src/pupnp/upnp/src/genlib/service_table/service_table.c [] []
/src/pupnp/upnp/inc/ithread.h [] []
/src/pupnp/ixml/src/node.c ['FuzzIxml'] ['FuzzIxml']
/src/pupnp/upnp/src/genlib/net/http/httpreadwrite.c [] []
/src/pupnp/upnp/src/gena/gena_callback2.c [] []
/src/pupnp/upnp/src/gena/gena_device.c [] []
/src/pupnp/upnp/src/genlib/net/http/webserver.c [] []
/src/pupnp/upnp/src/gena/gena_ctrlpt.c [] []
/src/pupnp/ixml/src/document.c ['FuzzIxml'] ['FuzzIxml']
/src/pupnp/upnp/src/api/UpnpStateVarComplete.c [] []
/src/pupnp/ixml/src/namedNodeMap.c [] []
/src/pupnp/upnp/src/api/UpnpActionRequest.c [] []
/src/pupnp/upnp/src/api/UpnpStateVarRequest.c [] []
/src/pupnp/upnp/src/api/UpnpDiscovery.c [] []
/src/pupnp/ixml/src/ixmlparser.c ['FuzzIxml'] ['FuzzIxml']
/src/pupnp/upnp/src/api/upnpdebug.c ['FuzzHttp'] ['FuzzHttp']
/src/pupnp/upnp/src/threadutil/ThreadPool.c [] []
/src/pupnp/upnp/src/api/UpnpExtraHeaders.c [] []
/src/pupnp/upnp/src/genlib/net/http/parsetools.c [] []
/src/pupnp/ixml/src/ixml.c ['FuzzIxml'] ['FuzzIxml']
/src/pupnp/upnp/src/ssdp/ssdp_ctrlpt.c [] []
/src/pupnp/ixml/src/nodeList.c [] []
/src/pupnp/upnp/src/threadutil/LinkedList.c ['FuzzHttp'] ['FuzzHttp']
/src/pupnp/ixml/src/attr.c ['FuzzIxml'] ['FuzzIxml']
/src/pupnp/upnp/src/genlib/net/sock.c [] []
/src/pupnp/upnp/src/api/upnpapi.c [] []
/src/pupnp/upnp/src/api/UpnpActionComplete.c [] []
/src/pupnp/upnp/src/threadutil/TimerThread.c [] []
/src/pupnp/upnp/src/api/UpnpFileInfo.c [] []
/src/pupnp/upnp/src/api/UpnpSubscriptionRequest.c [] []
/src/pupnp/upnp/src/uuid/sysdep.c [] []
/src/pupnp/upnp/src/genlib/miniserver/miniserver.c [] []
/src/pupnp/upnp/src/urlconfig/urlconfig.c [] []
/src/pupnp/upnp/src/api/UpnpEvent.c [] []
/src/pupnp/upnp/src/inc/sock.h [] []
/src/pupnp/upnp/src/genlib/util/membuffer.c ['FuzzHttp'] ['FuzzHttp']
/src/pupnp/upnp/src/soap/soap_device.c [] []
/src/pupnp/fuzzer/FuzzIxml.c ['FuzzIxml'] ['FuzzIxml']
/src/pupnp/fuzzer/FuzzHttp.c ['FuzzHttp'] ['FuzzHttp']
/src/pupnp/upnp/src/api/UpnpString.c [] []
/src/pupnp/upnp/src/genlib/net/http/httpparser.c ['FuzzHttp'] ['FuzzHttp']
/src/pupnp/upnp/src/inc/upnpapi.h [] []
/src/pupnp/upnp/src/uuid/uuid.c [] []
/src/pupnp/upnp/src/ssdp/ssdp_server.c [] []
/src/pupnp/upnp/src/genlib/util/util.c [] []
/src/pupnp/upnp/src/genlib/util/strintmap.c ['FuzzHttp'] ['FuzzHttp']
/src/pupnp/upnp/src/genlib/net/uri/uri.c ['FuzzHttp'] ['FuzzHttp']
/src/pupnp/upnp/src/soap/soap_ctrlpt.c [] []
/src/pupnp/upnp/src/uuid/md5.c [] []
/src/pupnp/upnp/src/genlib/util/list.c [] []
/src/pupnp/upnp/src/genlib/client_table/client_table.c [] []
/src/pupnp/upnp/src/threadutil/FreeList.c ['FuzzHttp'] ['FuzzHttp']
/src/pupnp/upnp/src/ssdp/SSDPResultData.c [] []
/src/pupnp/upnp/src/api/UpnpEventSubscribe.c [] []
/src/pupnp/upnp/src/genlib/net/http/statcodes.c [] []
/src/pupnp/upnp/src/ssdp/ssdp_device.c [] []
/src/pupnp/ixml/src/element.c ['FuzzIxml'] ['FuzzIxml']
/src/pupnp/upnp/src/ssdp/SSDPResultDataCallback.c [] []
/src/pupnp/upnp/src/genlib/client_table/GenlibClientSubscription.c [] []
/src/pupnp/ixml/src/ixmldebug.c ['FuzzIxml'] ['FuzzIxml']

Directories in report

Directory
/src/pupnp/upnp/src/genlib/net/http/
/src/pupnp/upnp/src/ssdp/
/src/pupnp/upnp/src/api/
/src/pupnp/upnp/src/genlib/net/uri/
/src/pupnp/fuzzer/
/src/pupnp/upnp/src/genlib/util/
/src/pupnp/upnp/src/threadutil/
/src/pupnp/upnp/src/genlib/client_table/
/src/pupnp/upnp/src/genlib/net/
/src/pupnp/ixml/src/
/src/pupnp/upnp/src/genlib/miniserver/
/src/pupnp/upnp/src/genlib/service_table/
/src/pupnp/upnp/src/soap/
/src/pupnp/upnp/src/uuid/
/src/pupnp/upnp/src/urlconfig/
/src/pupnp/upnp/inc/
/src/pupnp/upnp/src/inc/
/src/pupnp/upnp/src/gena/

Metadata section

This sections shows the raw data that is used to produce this report. This is mainly used for further processing and developer debugging.

Fuzzer Calltree file Program data file Coverage file
FuzzIxml fuzzerLogFile-0-j58ILlBnuF.data fuzzerLogFile-0-j58ILlBnuF.data.yaml FuzzIxml.covreport
FuzzHttp fuzzerLogFile-0-JN8VnZVG8h.data fuzzerLogFile-0-JN8VnZVG8h.data.yaml FuzzHttp.covreport