NRDAX-T0038 - Count Underflow Header Serving Amplification

Memory amplification (also response amplification) · P2P and gossip · mis-quantified bound · active · first seen 2026-07-07

provenance: Reproduced in NullRabbit's attack-reproduction pipeline

mechanism

CVE-2024-32972: eth GetBlockHeaders amount=0 → count-1 underflows to UINT64_MAX → bypasses maxHeadersServe → serves all headers to genesis → memory exhaustion (geth <1.13.15)

live exposure

No exposure data. Slashr ↗ has no risk signal mapped to this technique yet — absence of data is not absence of exposure.

research

In-depth write-ups of this attack on nullrabbit.ai.

How a zero-value GetBlockHeaders request underflows to serve go-ethereum's entire header chain (CVE-2024-32972) ↗

instances (1)

chain	primitive	fidelity	origin	reproducer (bundle)	source
ethereum	geth_getblockheaders_count_zero	lab	reverse-engineered-cve	geth_getblockheaders_count_zero	GHSA-4xc9-8hmq-j652 ↗

related (Memory amplification)

NRDAX-T0023 - Coalesced Packet Buffer Leak active NRDAX-T0025 - Compact Block Size Integer Overflow active NRDAX-T0042 - Crypto Frame Reassembly Buffer Exhaustion active NRDAX-T0046 - Decompression Bomb Resource Exhaustion active NRDAX-T0059 - Duplicate Transport Parameter Memory Leak active NRDAX-T0061 - Duplicate Tx Mempool Index Desync active NRDAX-T0071 - Ethash Verification Memory Exhaustion active NRDAX-T0095 - GraphQL Alias Query Amplification active

cite

https://nrdax.com/techniques/NRDAX-T0038

plain

NRDAX Registry. Technique NRDAX-T0038.

bibtex

@misc{nrdax_NRDAX_T0038,
  title = {Count Underflow Header Serving Amplification (NRDAX-T0038)},
  howpublished = {NRDAX Registry},
  url = {https://nrdax.com/techniques/NRDAX-T0038},
}

json (csl)

{
  "id": "nrdax-NRDAX-T0038",
  "type": "dataset",
  "title": "Count Underflow Header Serving Amplification (NRDAX-T0038)",
  "URL": "https://nrdax.com/techniques/NRDAX-T0038",
  "publisher": "NRDAX Registry"
}

badge

[![NRDAX-T0038 in the NRDAX registry](https://nrdax.com/badge/NRDAX-T0038.svg)](https://nrdax.com/techniques/NRDAX-T0038-count-underflow-header-serving-amplification)

use from the CLI

Retrieve or cite this technique from a script or the terminal with the NRDAX Python library & CLI.

Retrieve this technique

nrdax get NRDAX-T0038

Cite it (BibTeX)

nrdax cite NRDAX-T0038 --format bibtex

CLI guide → GitHub ↗