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JS: Improve XSS detection for serialize-javascript with tainted objects #19771

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Merged
Napalys merged 5 commits into from
Jun 17, 2025
Merged

JS: Improve XSS detection for serialize-javascript with tainted objects #19771

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a96ea18
JS: add test cases for `serialize-javascript` with tainted object pro…
Napalys Jun 16, 2025
5a107ec
JS: track taint through `serialize-javascript` calls with object argu…
Napalys Jun 16, 2025
fffbc0c
JS: add change note
Napalys Jun 16, 2025
eca69e1
JS: remove `serialize-javascript` from `JsonParsers.qll` as it is not…
Napalys Jun 16, 2025
fc0c8a8
JS: update change note
Napalys Jun 17, 2025
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4 changes: 4 additions & 0 deletions javascript/ql/lib/change-notes/2025-06-16-serialize-js.md
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@@ -0,0 +1,4 @@
---
category: minorAnalysis
---
* Improved XSS detection for `serialize-javascript` calls with tainted object properties.
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@erik-krogh erik-krogh Jun 17, 2025

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With your changes I don't feel this is entirely accurate.
Can you change to a more general statement that we track data through calls to serialize-javascript?

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@Napalys Napalys Jun 17, 2025

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Updated in fc0c8a8.

3 changes: 1 addition & 2 deletions javascript/ql/lib/semmle/javascript/JsonParsers.qll
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Expand Up @@ -33,8 +33,7 @@ private class PlainJsonParserCall extends JsonParserCall {
callee = DataFlow::moduleImport("parse-json") or
callee = DataFlow::moduleImport("json-parse-better-errors") or
callee = DataFlow::moduleImport("json-safe-parse") or
callee = AngularJS::angular().getAPropertyRead("fromJson") or
callee = DataFlow::moduleImport("serialize-javascript")
callee = AngularJS::angular().getAPropertyRead("fromJson")
)
}

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2 changes: 2 additions & 0 deletions javascript/ql/lib/semmle/javascript/JsonStringifiers.qll
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Expand Up @@ -27,6 +27,8 @@ class JsonStringifyCall extends DataFlow::CallNode {
)
or
this = Templating::getAPipeCall(["json", "dump"])
or
this = DataFlow::moduleImport("serialize-javascript").getACall()
}

/**
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34 changes: 34 additions & 0 deletions javascript/ql/test/query-tests/Security/CWE-079/ReflectedXss/ReflectedXss.expected
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Expand Up @@ -70,6 +70,8 @@
| tst2.js:76:12:76:18 | other.p | tst2.js:69:9:69:9 | p | tst2.js:76:12:76:18 | other.p | Cross-site scripting vulnerability due to a $@. | tst2.js:69:9:69:9 | p | user-provided value |
| tst2.js:88:12:88:12 | p | tst2.js:82:9:82:9 | p | tst2.js:88:12:88:12 | p | Cross-site scripting vulnerability due to a $@. | tst2.js:82:9:82:9 | p | user-provided value |
| tst2.js:89:12:89:18 | other.p | tst2.js:82:9:82:9 | p | tst2.js:89:12:89:18 | other.p | Cross-site scripting vulnerability due to a $@. | tst2.js:82:9:82:9 | p | user-provided value |
| tst2.js:101:12:101:17 | unsafe | tst2.js:93:9:93:9 | p | tst2.js:101:12:101:17 | unsafe | Cross-site scripting vulnerability due to a $@. | tst2.js:93:9:93:9 | p | user-provided value |
| tst2.js:113:12:113:17 | unsafe | tst2.js:105:9:105:9 | p | tst2.js:113:12:113:17 | unsafe | Cross-site scripting vulnerability due to a $@. | tst2.js:105:9:105:9 | p | user-provided value |
| tst3.js:6:12:6:12 | p | tst3.js:5:9:5:9 | p | tst3.js:6:12:6:12 | p | Cross-site scripting vulnerability due to a $@. | tst3.js:5:9:5:9 | p | user-provided value |
| tst3.js:12:12:12:15 | code | tst3.js:11:32:11:39 | reg.body | tst3.js:12:12:12:15 | code | Cross-site scripting vulnerability due to a $@. | tst3.js:11:32:11:39 | reg.body | user-provided value |
edges
Expand Down Expand Up @@ -239,6 +241,22 @@ edges
| tst2.js:86:15:86:27 | sortKeys(obj) [p] | tst2.js:86:7:86:27 | other [p] | provenance | |
| tst2.js:86:24:86:26 | obj [p] | tst2.js:86:15:86:27 | sortKeys(obj) [p] | provenance | |
| tst2.js:89:12:89:16 | other [p] | tst2.js:89:12:89:18 | other.p | provenance | |
| tst2.js:93:7:93:24 | p | tst2.js:99:51:99:51 | p | provenance | |
| tst2.js:93:9:93:9 | p | tst2.js:93:7:93:24 | p | provenance | |
| tst2.js:99:7:99:69 | unsafe | tst2.js:101:12:101:17 | unsafe | provenance | |
| tst2.js:99:16:99:69 | seriali ... true}) | tst2.js:99:7:99:69 | unsafe | provenance | |
| tst2.js:99:36:99:52 | {someProperty: p} [someProperty] | tst2.js:99:16:99:69 | seriali ... true}) | provenance | |
| tst2.js:99:51:99:51 | p | tst2.js:99:16:99:69 | seriali ... true}) | provenance | |
| tst2.js:99:51:99:51 | p | tst2.js:99:36:99:52 | {someProperty: p} [someProperty] | provenance | |
| tst2.js:105:7:105:24 | p | tst2.js:110:28:110:28 | p | provenance | |
| tst2.js:105:9:105:9 | p | tst2.js:105:7:105:24 | p | provenance | |
| tst2.js:110:7:110:29 | obj [someProperty] | tst2.js:111:36:111:38 | obj [someProperty] | provenance | |
| tst2.js:110:13:110:29 | {someProperty: p} [someProperty] | tst2.js:110:7:110:29 | obj [someProperty] | provenance | |
| tst2.js:110:28:110:28 | p | tst2.js:110:13:110:29 | {someProperty: p} [someProperty] | provenance | |
| tst2.js:110:28:110:28 | p | tst2.js:111:16:111:55 | seriali ... true}) | provenance | |
| tst2.js:111:7:111:55 | unsafe | tst2.js:113:12:113:17 | unsafe | provenance | |
| tst2.js:111:16:111:55 | seriali ... true}) | tst2.js:111:7:111:55 | unsafe | provenance | |
| tst2.js:111:36:111:38 | obj [someProperty] | tst2.js:111:16:111:55 | seriali ... true}) | provenance | |
| tst3.js:5:7:5:24 | p | tst3.js:6:12:6:12 | p | provenance | |
| tst3.js:5:9:5:9 | p | tst3.js:5:7:5:24 | p | provenance | |
| tst3.js:11:9:11:74 | code | tst3.js:12:12:12:15 | code | provenance | |
Expand Down Expand Up @@ -457,6 +475,22 @@ nodes
| tst2.js:88:12:88:12 | p | semmle.label | p |
| tst2.js:89:12:89:16 | other [p] | semmle.label | other [p] |
| tst2.js:89:12:89:18 | other.p | semmle.label | other.p |
| tst2.js:93:7:93:24 | p | semmle.label | p |
| tst2.js:93:9:93:9 | p | semmle.label | p |
| tst2.js:99:7:99:69 | unsafe | semmle.label | unsafe |
| tst2.js:99:16:99:69 | seriali ... true}) | semmle.label | seriali ... true}) |
| tst2.js:99:36:99:52 | {someProperty: p} [someProperty] | semmle.label | {someProperty: p} [someProperty] |
| tst2.js:99:51:99:51 | p | semmle.label | p |
| tst2.js:101:12:101:17 | unsafe | semmle.label | unsafe |
| tst2.js:105:7:105:24 | p | semmle.label | p |
| tst2.js:105:9:105:9 | p | semmle.label | p |
| tst2.js:110:7:110:29 | obj [someProperty] | semmle.label | obj [someProperty] |
| tst2.js:110:13:110:29 | {someProperty: p} [someProperty] | semmle.label | {someProperty: p} [someProperty] |
| tst2.js:110:28:110:28 | p | semmle.label | p |
| tst2.js:111:7:111:55 | unsafe | semmle.label | unsafe |
| tst2.js:111:16:111:55 | seriali ... true}) | semmle.label | seriali ... true}) |
| tst2.js:111:36:111:38 | obj [someProperty] | semmle.label | obj [someProperty] |
| tst2.js:113:12:113:17 | unsafe | semmle.label | unsafe |
| tst3.js:5:7:5:24 | p | semmle.label | p |
| tst3.js:5:9:5:9 | p | semmle.label | p |
| tst3.js:6:12:6:12 | p | semmle.label | p |
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2 changes: 2 additions & 0 deletions ...l/test/query-tests/Security/CWE-079/ReflectedXss/ReflectedXssWithCustomSanitizer.expected
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Expand Up @@ -68,5 +68,7 @@
| tst2.js:76:12:76:18 | other.p | Cross-site scripting vulnerability due to $@. | tst2.js:69:9:69:9 | p | user-provided value |
| tst2.js:88:12:88:12 | p | Cross-site scripting vulnerability due to $@. | tst2.js:82:9:82:9 | p | user-provided value |
| tst2.js:89:12:89:18 | other.p | Cross-site scripting vulnerability due to $@. | tst2.js:82:9:82:9 | p | user-provided value |
| tst2.js:101:12:101:17 | unsafe | Cross-site scripting vulnerability due to $@. | tst2.js:93:9:93:9 | p | user-provided value |
| tst2.js:113:12:113:17 | unsafe | Cross-site scripting vulnerability due to $@. | tst2.js:105:9:105:9 | p | user-provided value |
| tst3.js:6:12:6:12 | p | Cross-site scripting vulnerability due to $@. | tst3.js:5:9:5:9 | p | user-provided value |
| tst3.js:12:12:12:15 | code | Cross-site scripting vulnerability due to $@. | tst3.js:11:32:11:39 | reg.body | user-provided value |
26 changes: 25 additions & 1 deletion javascript/ql/test/query-tests/Security/CWE-079/ReflectedXss/tst2.js
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Expand Up @@ -87,4 +87,28 @@ app.get('/baz', function(req, res) {

res.send(p); // $ Alert
res.send(other.p); // $ Alert
});
});

app.get('/baz', function(req, res) {
let { p } = req.params; // $ Source

var serialized = serializeJavaScript(p);

res.send(serialized);

var unsafe = serializeJavaScript({someProperty: p}, {unsafe: true});

res.send(unsafe); // $ Alert
});

app.get('/baz', function(req, res) {
let { p } = req.params; // $ Source

var serialized = serializeJavaScript(p);

res.send(serialized);
let obj = {someProperty: p};
var unsafe = serializeJavaScript(obj, {unsafe: true});

res.send(unsafe); // $ Alert
});