CVE-2020-26240: Github.com/ethereum/go ethereum Erroneous Proof Of Work Calculation Vulnerability
MODERATECVE-2020-26240 is a MODERATE (CVSS 5.3) erroneous proof of work calculation vulnerability (CWE-682: Incorrect Calculation) affecting Github.com/ethereum/go ethereum libraries in the Go ecosystem. The issue involves erroneous proof of work calculation in geth. Remediation is available by upgrading affected packages to version 1.9.24.
CVE-2020-26240 at a Glance
Security Impact
CVSS: 5.3
The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:H/A:N).
How to Fix CVE-2020-26240
To remediate this vulnerability, upgrade all affected Github.com/ethereum/go ethereum dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.
Upgrade github.com/ethereum/go-ethereum to 1.9.24Run the following command in your project directory to verify that all resolved dependencies use the patched release:
inspect dependencies for github.com/ethereum/go-ethereumHow to Check if You Are Affected
To determine whether your application is affected by CVE-2020-26240, inspect your project dependencies for Github.com/ethereum/go ethereum:
inspect dependencies for github.com/ethereum/go-ethereumAnalyze the terminal output to locate any version of Github.com/ethereum/go ethereum in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 1.9.24), your application is affected.
Note: Verify declared build manifests and deployed runtime container environments.
Technical Details
Vulnerability Mechanism & Technical Analysis
This vulnerability is classified under CWE-682: Incorrect Calculation, where the product performs a calculation that generates incorrect or unintended results that are later used in security-critical decisions or resource management. In Github.com/ethereum/go ethereum, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.
Source Advisory Statement
CVE-2020-26240 Affected Github.com/ethereum/go ethereum Versions
1 component(s)| Product / Package | Ecosystem | Affected Versions | Fixed Version |
|---|---|---|---|
|
github.com/ethereum/go-ethereum
|
Go |
< 1.9.24
|
1.9.24
|
References
Frequently Asked Questions
What is CVE-2020-26240?
Which Github.com/ethereum/go ethereum versions are affected?
What version fixes CVE-2020-26240?
Is github.com/ethereum/go-ethereum affected?
What is the CVSS score of CVE-2020-26240?
What CWE is associated with CVE-2020-26240?
How can I check Go dependencies for CVE-2020-26240?
Machine-readable OSV JSON
OSV v1.5 Schema
{
"schema_version" : "1.4.0",
"id" : "GHSA-v592-xf75-856p",
"modified" : "2025-01-30T14:39:18Z",
"published" : "2021-06-29T21:12:56Z",
"aliases" : [ "CVE-2020-26240" ],
"summary" : "Erroneous Proof of Work calculation in geth",
"details" : "### Impact\nAn ethash mining DAG generation flaw in Geth could cause miners to erroneously calculate PoW in an upcoming epoch (estimated early January, 2021). This happened on the ETC chain on 2020-11-06. This issue is relevant only for miners, non-mining nodes are unaffected.\n\n### Patches\nThis issue is also fixed as of 1.9.24. Thanks to @slavikus for bringing the issue to our attention and writing the fix. \n\n### Workarounds\nThis PR implements a patch: https://github.com/ethereum/go-ethereum/pull/21793 \n\n### References\nhttps://blog.ethereum.org/2020/11/12/geth_security_release/\n\n### For more information\nIf you have any questions or comments about this advisory:\n* Open an issue in [go-ethereum](https://github.com/ethereum/go-ethereum)\n* Email us at [security@ethereum.org](mailto:security@ethereum.org)",
"severity" : [ {
"type" : "CVSS_V3",
"score" : "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:H/A:N"
} ],
"affected" : [ {
"package" : {
"ecosystem" : "Go",
"name" : "github.com/ethereum/go-ethereum"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "0"
}, {
"fixed" : "1.9.24"
} ]
} ]
} ],
"references" : [ {
"type" : "WEB",
"url" : "https://github.com/ethereum/go-ethereum/security/advisories/GHSA-v592-xf75-856p"
}, {
"type" : "ADVISORY",
"url" : "https://nvd.nist.gov/vuln/detail/CVE-2020-26240"
}, {
"type" : "WEB",
"url" : "https://github.com/ethereum/go-ethereum/pull/21793"
}, {
"type" : "WEB",
"url" : "https://github.com/ethereum/go-ethereum/commit/d990df909d7839640143344e79356754384dcdd0"
}, {
"type" : "WEB",
"url" : "https://blog.ethereum.org/2020/11/12/geth_security_release"
}, {
"type" : "PACKAGE",
"url" : "https://github.com/ethereum/go-ethereum"
} ],
"database_specific" : {
"cwe_ids" : [ "CWE-682" ],
"severity" : "MODERATE",
"github_reviewed" : true,
"github_reviewed_at" : "2021-05-21T21:52:58Z",
"nvd_published_at" : null
}
}