# Parser resource exhaustion and decompression amplification

A small accepted input causes disproportionate CPU, memory, recursion, or expanded output consumption without effective limits at the relevant consumer.

**Candidate CWE:** [CWE-400](https://cwe.mitre.org/data/definitions/400.html)

## Test hypothesis

Measure a few progressively sized synthetic local inputs under fixed time/memory bounds, then stop once scaling and the missing limit are established. Compare a normal input and configured size/depth/expansion limits. Check whether the public consumer imposes effective limits before the library runs.

## Evidence required

Input sizes, repeatable time/RSS/output measurements, tool/build configuration, parser call path, and enforced versus missing bounds. Report local amplification and exposed workload; never infer service-wide denial from one slow call alone.

## Rule out false positives

Expected work on proportionately large input, a tight upstream limit, a lab configured without documented production bounds, or timeouts caused by unrelated I/O.

## Playbook and command references

- [Libraries and parsers: bounded fuzzing to a minimal reproducer](https://bug-bounty-field-manual.kmahshooq.chatgpt.site/modules/parser-fuzzing.html) — Build a realistic local harness, instrument the target, bound fuzzing resources, and turn unique faults into defensible library or consumer reports.
- [Dependencies: from advisory match to reachable impact](https://bug-bounty-field-manual.kmahshooq.chatgpt.site/modules/dependency-reachability.html) — Separate composition, advisory matching, runtime reachability, and exploit prerequisites so dependency reports describe product impact.

[Find the associated command snippets](https://bug-bounty-field-manual.kmahshooq.chatgpt.site/commands.html?q=Libraries%20and%20parsers%3A%20bounded%20fuzzing%20to%20a%20minimal%20reproducer)

## Referenced by these target playbooks

[OSS & self-hosted](https://bug-bounty-field-manual.kmahshooq.chatgpt.site/oss.html) · [Web & API](https://bug-bounty-field-manual.kmahshooq.chatgpt.site/web-api.html) · [Desktop & extensions](https://bug-bounty-field-manual.kmahshooq.chatgpt.site/desktop.html) · [Mobile](https://bug-bounty-field-manual.kmahshooq.chatgpt.site/mobile.html) · [Network services](https://bug-bounty-field-manual.kmahshooq.chatgpt.site/network.html) · [AI, agents & MCP](https://bug-bounty-field-manual.kmahshooq.chatgpt.site/ai.html)

## Report checklist

- [ ] Capture the affected version, configuration, identities, and object ownership.
- [ ] Preserve a valid baseline and a negative control.
- [ ] Reproduce the forbidden data access, action, or state change on controlled fixtures.
- [ ] Explain the intended security rule and why the observed behavior violates it.
- [ ] State prerequisites, uncertainty, cleanup, and the smallest demonstrated impact.

## Conditional ATT&CK mapping

No direct ATT&CK mapping selected. Record the weakness and demonstrated impact without forcing an adversary-behavior classification. See the [mapping guide](https://bug-bounty-field-manual.kmahshooq.chatgpt.site/attack.html).

## Primary references

- [MITRE CWE-400](https://cwe.mitre.org/data/definitions/400.html)

[Back to the complete vulnerability catalog](https://bug-bounty-field-manual.kmahshooq.chatgpt.site/vulnerabilities.html)