CVE-2019-25220: bitcoin core DoS — Fix

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.

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CVSS v3.1 Score

7.5

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Weakness Type (CWE)

CWE-770 CWE-770

Affected Products

Vendor	Product	Versions
bitcoin	bitcoin_core	< 24.0.1

References

Advisories & Patches

https://bitcoincore.org/en/2024/09/18/disclose-headers-oom

Other References

https://en.bitcoin.it/wiki/Common_Vulnerabilities_and_Exposures https://lists.linuxfoundation.org/pipermail/bitcoin-dev/2019-October/017354.html

Frequently Asked Questions

What is CVE-2019-25220? +

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. It has a CVSS v3.1 base score of 7.5 (HIGH).

How severe is CVE-2019-25220? +

CVE-2019-25220 has a CVSS v3.1 score of 7.5 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching.

What products are affected by CVE-2019-25220? +

CVE-2019-25220 affects products from bitcoin, specifically: bitcoin_core. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2019-25220? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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CVE-2019-25220