open/llm-security
1
0
Fork 0
Code Issues Releases 1 Activity

fix(llm-security): scanner robustness — ReDoS, MCP-stdout DoS, redirect loop, atomic writes (#24,#53,#31,#25,#51)

Browse source 
#24 the HTML-obfuscation injection patterns had overlapping unbounded runs plus a required closing quote, so a non-closing input backtracked O(N^2) (~28.7s at the 512KB cap); quantifiers bounded, pathological input now 4ms. #53 mcp-live-inspect buffered MCP-server stdout via readline with no cap, so a hostile stdio server could exhaust memory / throw an uncaught RangeError; replaced with manual line buffering capped at 4MB that rejects pending RPCs and destroys stdout. #31 vsix-fetch's same-host redirect follower had no depth cap (loop hang); added depth>=5 cap mirroring the sibling fetcher.

#25/#51 mcp-description-cache and skill-registry wrote JSON via bare writeFileSync (non-atomic: concurrent load-modify-save loses updates, a torn read silently yields an empty registry); both now write a temp file then renameSync. Suite 1931/0.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Claude-Session: https://claude.ai/code/session_01TcQyMTQfyrsAapaCMPxTtQ
This commit is contained in:
Kjell Tore Guttormsen 2026-07-18 10:15:11 +02:00
commit 207385fbbe
10 changed files with 251 additions and 19 deletions
Download patch file Download diff file Expand all files Collapse all files

8
scanners/lib/skill-registry.mjs
View file

@ -4,7 +4,7 @@
// Zero external dependencies.
import { createHash } from 'node:crypto';
import { existsSync, mkdirSync, readFileSync, writeFileSync, readdirSync, statSync } from 'node:fs';
import { existsSync, mkdirSync, readFileSync, writeFileSync, readdirSync, statSync, renameSync } from 'node:fs';
import { join, resolve, relative, dirname, basename, extname } from 'node:path';
import { fileURLToPath } from 'node:url';
@ -259,7 +259,11 @@ export function saveRegistry(registry, pluginRoot) {
registry.updated = new Date().toISOString();
registry.entry_count = Object.keys(registry.entries).length;
writeFileSync(filePath, JSON.stringify(registry, null, 2) + '\n');
// Atomic write (v7.8.3 #51): temp file + rename — a torn write would
// parse-fail in loadRegistry and silently reset to an empty registry.
const tmpPath = `${filePath}.tmp-${process.pid}-${Date.now()}`;
writeFileSync(tmpPath, JSON.stringify(registry, null, 2) + '\n');
renameSync(tmpPath, filePath);
return filePath;
}