CVE-2021-21369

mediumpriority · track · 27EPSS 0.017 · 77 %ileEUUS
grimoire priorityP3 · Track
Exploitable?
—
no known exploitation
Likely / severe?
1.67% (77th) EPSS
CVSS 4 · medium
Is it mine?
2 products
Check your exposure
Who says so?
3 sources
cnnvd · enisa_euvd · nvd

EPSS · scored 2026-10-28

Hyperledger Besu is an open-source, MainNet compatible, Ethereum client written in Java. In Besu before version 1.5.1 there is a denial-of-service vulnerability involving the HTTP JSON-RPC API service. If username and password authentication is enabled for the HTTP JSON-RPC API service, then prior to making any requests to an API endpoint the requestor must use the login endpoint to obtain a JSON web token (JWT) using their credentials. A single user can readily overload the login endpoint with invalid requests (incorrect password). As the supplied password is checked for validity on the main vertx event loop and takes a relatively long time this can cause the processing of other valid requests to fail. A valid username is required for this vulnerability to be exposed. This has been fixed in version 1.5.1.

01

cvss

Technical severity, 0–10. One row per scoring source.

6.5
010

base score 0–10 · higher = more severe · hover a vector to decode

v2.04mediumAV:N/AC:L/Au:S/C:N/I:N/A:Pprimary · NVD / NIST USexploitability 8 · impact 2.9
v3.16.5mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:Hprimary · NVD / NIST USexploitability 2.8 · impact 3.6
v3.16.5mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:Hsecondary · ENISA EU
v3.16.5mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:Hsecondary · security-advisories@github.comexploitability 2.8 · impact 3.6
v3.16mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)
02

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-400US
03

affected products (2)

Products and version ranges known to be affected.

04

also known as (2)

Other names and identifiers for this entity.

05

sources

Which sources assert this record, and when.

cnnvdenisa_euvdnvdNVDCVE.orgMITRE
published 2021-03-09modified 2026-06-17
06

references (13)

External citations — patches, advisories, analysis.

scry

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