The Bitcoin Proof-of-Work algorithm does not consider a certain attack methodology related to 80-byte block headers with a variety of initia
The Bitcoin Proof-of-Work algorithm does not consider a certain attack methodology related to 80-byte block headers with a variety of initial 64-byte chunks followed by the same 16-byte chunk, multiple candidate root values ending with the same 4 bytes, and calculations involving sqrt numbers. This violates the security assumptions of (1) the choice of input, outside of the dedicated nonce area, fed into the Proof-of-Work function should not change its difficulty to evaluate and (2) every Proof-of-Work function execution should be independent. NOTE: a number of persons feel that this methodology is a benign mining optimization, not a vulnerability
- Published
- May 24, 2017
- Updated
- Jun 16, 2026
- EPSS
- 3.3% · 88th percentile
- CWE
- CWE-338
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Report tools
Action score
31
Monitor
Low priority for now.
- CVSS
- 30 / 40 · 7.5 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 1 / 30 · 3.3%
CISA SSVC decision
- Exploitation
- none
- Automatable
- yes
- Technical impact
- partial
Vulnrichment: CISA's decision-tree inputs.
Affected systems
| Vendor | Product | CPE |
|---|---|---|
| bitcoin | bitcoin | cpe:2.3:a:bitcoin:bitcoin |
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- bitcoin bitcoinall versions
Same product
bitcoin: all recordsOther highest-scoring records for the same primary product.
- CVE-2021-3401Bitcoin Core before 0.19.0 might allow remote attackers to execute arbitrary code when another application unsafely passes the -platformplug42Plan
- CVE-2021-31876Bitcoin Core 0.12.0 through 0.21.1 does not properly implement the replacement policy specified in BIP125, which makes it easier for attacke26Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
No fix version is recorded for this entry. Check the references for vendor advisories.
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
No dated events beyond publication.
FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
No commit or PR link among the references.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
No credits in the CNA record.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
No nightly-computed relations.
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
—
Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
Technical details
Attack conditions
- Anyone who can reach it over the internet can trigger it.
- No account or password is required.
- No user action is required.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- high · data can be read
- Integrity
- none
- Availability
- none
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- High
- Integrity impact
- None
- Availability impact
- None
Weakness class (CWE)
CWE-338 · Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG)CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
nvd-secondary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
MITRE has no CAPEC/ATT&CK mapping for this CWE.
Noroxi analysis
No Noroxi analysis for this record yet
We don't hand-write analysis for all 385,000+ vulnerabilities; that wouldn't be honest. For notable, high-impact vulnerabilities our team writes the mechanism, detection and remediation steps.
We use this product, ask for helpChange log
No changes recorded on tracked fields yet. Score, KEV, exploit maturity and fix status changes appear here.
References
- www.mit.edu/~jlrubin//public/pdfs/Asicboost.pdf
- www.securityfocus.com/bid/98657
- arxiv.org/ftp/arxiv/papers/1604/1604.00575.pdf
- lists.linuxfoundation.org/pipermail/bitcoin-dev/2017-April/013996.html
- lists.linuxfoundation.org/pipermail/bitcoin-dev/2017-May/014349.html
- lists.linuxfoundation.org/pipermail/bitcoin-dev/2017-May/014351.html
- lists.linuxfoundation.org/pipermail/bitcoin-dev/2017-May/014352.html
Vendor advisories and official records. Exploit/PoC links are deliberately left out.