CVE-2019-25220: bitcoin bitcoin_core
Vulnerability summary
CVE-2019-25220 is a high (CVSS 7.5) vulnerability in bitcoin bitcoin_core. EPSS estimates a 0.82% chance of exploitation in the next 30 days, higher than 57.1% of scored vulnerabilities.
Severe, CVSS 7.5 (CVE.org); no exploitation reported by the 5 checked sources; EPSS 1% (FIRST, 03-11-2026)
Source freshness unavailable
How is this decided?Timeline
- 18-11-2024PublishedVulnerability first disclosed.
- 18-11-2024Last modifiedVulnerability information updated.
Description
Bitcoin Core before 24.0.1 allows remote attackers to cause a denial of service (daemon crash) via a flood of low-difficulty header chains (aka a "Chain Width Expansion" attack) because a node does not first verify that a presented chain has enough work before committing to store it.
CVSS metrics
2 scores · 2 sources · 1 version- NVDNIST7.5HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS trend
Probability
0.82%
Chance of exploitation in the next 30 days
Percentile
57%
Versus all other CVEs
30-day change
No change 0.00 pp
From 0.82% on 04-10-2026
Known exploited
Compare KEV catalogsNot in the CISA KEV catalog.
Not in the ENISA CNW catalog.
Not in the CIRCL catalog.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Known conditions: network-reachable, no authentication, no user interaction (CVSS vector). Other conditions: not stated in public data.
Bitcoin1 product
- bitcoin_core< 24.0.1
1 vendor · 1 product
References
3 links- en.bitcoin.it/wiki/Common_Vulnerabilities_and_ExposuresThird Party Advisory
- bitcoincore.org/en/2024/09/18/disclose-headers-oomVendor Advisory