#Output Formats
Nyx supports three output formats, selected with --format or output.default_format in config.
#Console (default)
Human-readable, color-coded output to stdout. Status messages go to stderr.
[HIGH] taint-unsanitised-flow (source 5:11) src/handler.rs:12:5 (Score: 76, Confidence: High)
Source: env::var("CMD") → Command::new("sh").arg("-c")
[MEDIUM] cfg-unguarded-sink src/handler.rs:12:5 (Score: 35, Confidence: Medium)
[LOW] rs.quality.unwrap src/lib.rs:88:5 (Score: 10, Confidence: High)
#Severity indicators
| Tag | Color | Meaning |
|---|---|---|
[HIGH] |
Red, bold | Critical -- likely exploitable |
[MEDIUM] |
Orange, bold | Important -- may be exploitable |
[LOW] |
Muted blue-gray | Informational -- code quality or weak signal |
#Evidence fields
Taint and state findings include structured evidence:
| Label | Meaning |
|---|---|
| Source | Where tainted data originated (function name + location) |
| Sink | Where the dangerous operation happens |
| Path guard | Type of validation predicate protecting the path |
#Score
When attack-surface ranking is enabled (default), each finding shows a Score value. Higher scores indicate greater exploitability. See Detector Overview for the scoring formula.
#Rollup findings
High-frequency LOW Quality findings (e.g. rs.quality.unwrap) are grouped into rollup findings by (file, rule):
21:10 ● [LOW] rs.quality.unwrap
rs.quality.unwrap (38 occurrences)
Examples: 21:10, 50:10, 79:10, 105:10, 134:10
Run: nyx scan --show-instances rs.quality.unwrap
Rollups count as one finding for LOW budget enforcement. Use --show-instances <RULE> to expand a specific rule or --all to disable rollups entirely.
#Suppression footer
When findings are suppressed by the prioritization pipeline, a footer is shown:
Suppressed 195 LOW/Quality findings.
Active filters:
include_quality = false
max_low = 20
max_low_per_file = 1
max_low_per_rule = 10
Use --include-quality, --max-low, or --all to adjust.
#JSON
Machine-readable JSON array. Each finding is an object:
[
{
"path": "src/handler.rs",
"line": 12,
"col": 5,
"severity": "High",
"id": "taint-unsanitised-flow (source 5:11)",
"path_validated": false,
"labels": [
["Source", "env::var(\"CMD\") at 5:11"],
["Sink", "Command::new(\"sh\").arg(\"-c\")"]
],
"confidence": "High",
"evidence": {
"source": {
"path": "src/handler.rs",
"line": 5,
"col": 11,
"kind": "source",
"snippet": "env::var(\"CMD\")"
},
"sink": {
"path": "src/handler.rs",
"line": 12,
"col": 5,
"kind": "sink",
"snippet": "Command::new(\"sh\")"
},
"notes": ["source_kind:EnvironmentConfig"]
},
"rank_score": 76.0,
"rank_reason": [
["severity_base", "60"],
["analysis_kind", "10"],
["source_kind", "5"],
["evidence_count", "1"]
]
}
]
#Field descriptions
| Field | Type | Always present | Description |
|---|---|---|---|
path |
string | yes | File path relative to scan root |
line |
int | yes | 1-indexed line number |
col |
int | yes | 1-indexed column number |
severity |
string | yes | "High", "Medium", or "Low" |
id |
string | yes | Rule ID |
category |
string | yes | Finding category: "Security", "Reliability", or "Quality" |
path_validated |
bool | no | True if guarded by validation predicate |
guard_kind |
string | no | Predicate type (e.g. "NullCheck", "ValidationCall") |
message |
string | no | Human-readable context (state analysis findings) |
labels |
array | no | Array of [label, value] pairs for console display |
confidence |
string | no | Confidence level: "Low", "Medium", or "High" |
evidence |
object | no | Structured evidence (source/sink spans, state, notes) |
rank_score |
float | no | Attack-surface score (omitted when ranking disabled) |
rank_reason |
array | no | Score breakdown (omitted when ranking disabled) |
rollup |
object | no | Rollup data when findings are grouped (see below) |
Fields marked "no" are omitted when empty/null/false to keep output compact.
#Confidence levels
| Level | Meaning |
|---|---|
High |
Strong signal -- taint-confirmed flow, definite state violation |
Medium |
Moderate signal -- resource leak, path-validated taint, CFG structural |
Low |
Weak signal -- AST pattern match, possible resource leak, degraded analysis |
#Evidence object
The evidence field provides structured provenance data:
| Field | Type | Description |
|---|---|---|
source |
object | Source span (path, line, col, kind, snippet) |
sink |
object | Sink span (path, line, col, kind, snippet) |
guards |
array | Validation guard spans |
sanitizers |
array | Sanitizer spans |
state |
object | State-machine evidence (machine, subject, from_state, to_state) |
notes |
array | Free-form notes (e.g. "source_kind:UserInput", "path_validated") |
All fields are omitted when empty/null.
#Rollup object
When a finding is a rollup (grouped from multiple occurrences), the rollup field is present:
{
"rollup": {
"count": 38,
"occurrences": [
{ "line": 21, "col": 10 },
{ "line": 50, "col": 10 },
{ "line": 79, "col": 10 }
]
}
}
| Field | Type | Description |
|---|---|---|
count |
int | Total number of occurrences |
occurrences |
array | First N example locations (controlled by rollup_examples) |
#SARIF (Static Analysis Results Interchange Format)
SARIF 2.1.0 JSON, suitable for GitHub Code Scanning and other SARIF-compatible tools.
nyx scan . --format sarif > results.sarif
The SARIF output includes:
- Tool metadata -- Nyx name and version
- Rules -- Rule ID, description, severity mapping
- Results -- One result per finding with location, message, and properties
- Properties -- Each result includes
categoryand optionallyconfidenceandrollup.count - Related locations -- Rollup findings include example locations in
relatedLocations - Artifacts -- File paths referenced by findings
#GitHub Code Scanning integration
- name: Run Nyx
run: nyx scan . --format sarif > results.sarif
- name: Upload SARIF
uses: github/codeql-action/upload-sarif@v3
with:
sarif_file: results.sarif
#Exit Codes
| Code | Meaning |
|---|---|
0 |
Scan completed successfully; no findings matched --fail-on threshold |
1 |
--fail-on threshold breached (at least one finding meets or exceeds the specified severity) |
| Non-zero | Error (I/O, config, database, parse error) |
Without --fail-on, Nyx always exits 0 on a successful scan regardless of findings count.
#Severity Levels
| Level | Description | Typical rules |
|---|---|---|
| High | Critical vulnerabilities -- likely exploitable | Command injection, unsafe deserialization, banned C functions, taint-confirmed flows with user input sources |
| Medium | Important issues -- may be exploitable with additional context | SQL concatenation, XSS sinks, reflection, unguarded sinks, resource leaks |
| Low | Informational -- code quality or weak signals | Weak crypto algorithms, insecure randomness, unwrap()/panic!(), type-safety escapes |
#Non-production severity downgrade
By default, findings in paths matching common non-production patterns (tests/, test/, vendor/, build/, examples/, benchmarks/) are downgraded by one tier:
- High → Medium
- Medium → Low
- Low → Low (unchanged)
Use --keep-nonprod-severity to disable this behavior.
#Inline Suppressions
Suppress specific findings directly in source code using nyx:ignore comments. Suppressed findings are excluded from output, severity counts, and --fail-on checks by default.
#Comment syntax
| Language | Comment styles |
|---|---|
| Rust, C, C++, Java, Go, JS, TS | // nyx:ignore ... or /* nyx:ignore ... */ |
| Python, Ruby | # nyx:ignore ... |
| PHP | // nyx:ignore ..., # nyx:ignore ..., or /* nyx:ignore ... */ |
#Directive forms
x = dangerous() # nyx:ignore taint-unsanitised-flow ← suppresses this line
# nyx:ignore-next-line taint-unsanitised-flow
x = dangerous() ← suppresses this line
nyx:ignore <RULE_ID>-- suppresses findings on the same line as the comment.nyx:ignore-next-line <RULE_ID>-- suppresses findings on the next line.- For taint findings, the primary line is the sink line (the
linefield in output).
#Rule ID matching
- Case-sensitive, exact match after canonicalization.
- Comma-separated:
nyx:ignore rule-a, rule-b - Wildcard suffix:
nyx:ignore rs.quality.*matches any ID starting withrs.quality. - Taint IDs are canonicalized:
nyx:ignore taint-unsanitised-flowmatchestaint-unsanitised-flow (source 5:1)(parenthetical suffix stripped).
#Console behavior
- Default: suppressed findings are hidden entirely.
--show-suppressed: suppressed findings appear dimmed with[SUPPRESSED]tag. Summary shows"N issues (M suppressed)".
#JSON / SARIF behavior
- Default: suppressed findings are excluded from JSON/SARIF output.
--show-suppressed: suppressed findings are included with additional fields:
{
"suppressed": true,
"suppression": {
"kind": "SameLine",
"matched_pattern": "taint-unsanitised-flow",
"directive_line": 42
}
}
#Exit code
Suppressed findings do not trigger --fail-on. A scan with only suppressed findings exits 0.
#Rule ID Format
| Prefix | Detector | Example |
|---|---|---|
taint-* |
Taint analysis | taint-unsanitised-flow (source 5:11) |
cfg-* |
CFG structural | cfg-unguarded-sink, cfg-auth-gap |
state-* |
State model | state-use-after-close, state-resource-leak |
<lang>.*.* |
AST patterns | rs.memory.transmute, js.code_exec.eval |
See the Rule Reference for a complete listing.