pegjs — Greenflagged

Parser generator for JavaScript

Supply chain provenance

Status for the latest visible version.

No SLSA provenance npm registry signatures gitHead linked

Without SLSA provenance there is no cryptographic link between this tarball and the public source — the axios compromise (March 2026) relied on exactly this gap.

Maintainers

dmajda

Keywords

parser generatorPEG

Accepted risks

Findings the reviewer chose to accept rather than block on.

Source	Rule	Reason	Accepted by	When
source-diff	obfuscated-file:lib/parser.js	AI (source-diff): lib/parser.js is PEG.js's self-hosted generated parser; long lines are inherent to generated parser output, not obfuscation.	ai	2026/04/24
source-diff	net-exec-file:lib/compiler/passes/generate-javascript.js	AI (source-diff): False positive: this is PEG.js's parser code generator — it constructs JS source strings for parsers, no network calls present.	ai	2026/04/24
source-diff	net-exec-file:lib/compiler/passes/generate-js.js	AI (source-diff): Core code generation pass of a parser generator; String.fromCharCode for bytecode encoding, not malicious network/exec activity.	ai	2026/04/23
semgrep	semgrep:eval-usage	AI (semgrep): eval() is PEG.js's documented mechanism to compile grammars into runnable parsers at runtime; fundamental to the library's design.	ai	2026/04/23
provenance	no-provenance	AI (provenance): Package predates Sigstore provenance; long-established publisher with consistent history.	ai	2026/04/23

Versions (showing 7 of 7)

Version	Deps	Published
0.10.0	0 / 5	2016-08-19
0.9.0	0 / 3	2015-08-30
0.8.0	0 / 3	2013-12-24
0.7.0	0 / 2	2012-04-18
0.6.2	0 / 2	2011-08-20
0.6.1	0 / 2	2011-04-14
0.6.0	0 / 2	2011-04-14

v0.10.0

2 findings

HIGH New file with network + code execution: lib/compiler/passes/generate-js.js source-diff

Newly added file contains both network calls and dynamic code execution. This is a hallmark of dropper/loader malware.

LOW No provenance attestation provenance

Package was published without Sigstore provenance. Consider requesting the maintainer enable provenance via CI/CD.

v0.9.0

3 findings

HIGH New obfuscated file: lib/parser.js source-diff

Newly added source file contains lines over 3000 chars, suggesting minified or obfuscated code. New obfuscated files are a strong attack indicator.

HIGH New file with network + code execution: lib/compiler/passes/generate-javascript.js source-diff

Newly added file contains both network calls and dynamic code execution. This is a hallmark of dropper/loader malware.