T09 · Insecure Skill Coding Practices
Warning
- Location
- scripts/log_analyzer.py:244
- Finding
- Unbounded Memory Consumption When Parsing Large Log Files## Vulnerability Details **File Location**: `scripts/log_analyzer.py`, lines 244-260 **Vulnerability Type**: Uncontrolled resource consumption / memory exhaustion **Risk Level**: Medium ```python last_entry = None with open(self.log_file, 'r', encoding='utf-8', errors='ignore') as f: for line_num, line in enumerate(f, 1): line = line.strip() if not line: # Empty lines may also mark the end of an exception self.exception_tracker.process_line(line, line_num, last_entry) continue entry = self.parse_line(line, line_num) if entry: self.entries.append(entry) last_entry = entry else: # Nonstandard log lines, such as tracebacks, are still inspected self.exception_tracker.process_line(line, line_num, last_entry) ``` ### Technical Analysis The analyzer processes the input incrementally but retains every successfully parsed log entry in `self.entries`. Each entry contains the full message and other parsed fields. Additional collections, including issue lists, exception records, performance data, and module statistics, may retain references or copies derived from the same input. No limit is imposed on input file size, line length, parsed-entry count, traceback size before finalization, or total memory consumption. Consequently, memory usage grows approximately in proportion to attacker-controlled input size. Calling `line.strip()` also creates a new string for each line, and an exceptionally long individual line can cause a significant temporary allocation. This is especially relevant because arbitrary or large log files are the intended input to the Skill. The documentation only warns that files larger than 10 MB may take longer; it does not enforce a safe upper bound. ### Attack Path 1. An attacker creates or influences a log file containing a very large number of syntactically valid ent ...[truncated 1177 chars]
- Remediation
- ## Remediation Suggestions - Replace full-entry retention with streaming aggregation. Update counters, time ranges, performance statistics, and module statistics as each line is parsed rather than storing every entry. - Retain only a configurable, bounded number of examples for each issue category and exception type, such as the first or most recent three records. - Enforce a configurable maximum input size before opening the file. Reject oversized files with a clear error or require explicit user authorization to process them. - Enforce maximum line and message lengths. Read bounded chunks or truncate oversized messages before parsing and storing them. - Bound traceback accumulation while processing it, rather than truncating only when the exception is finalized. - Cap the number of stored exceptions and source-file frames. - Catch `MemoryError` at the command-line boundary and terminate cleanly with a nonzero exit status, while recognizing that prevention through strict bounds is preferable. - Document resource limits and provide configuration options suitable for constrained Agent or container environments.