CVE-2020-15112: Improper Input Validation in etcd

Severity: medium (CVSS 6.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2020-08-05 · updated 2026-06-17
Weakness: CWE-20

Description

In etcd before versions 3.3.23 and 3.4.10, it is possible to have an entry index greater then the number of entries in the ReadAll method in wal/wal.go. This could cause issues when WAL entries are being read during consensus as an arbitrary etcd consensus participant could go down from a runtime panic when reading the entry.

Affected products

etcd-io etcd: before 3.3.23; from 3.4.0 before 3.4.10 — fixed in 3.3.23, 3.4.10
Fedoraproject Fedora: 32

How to fix

Upgrade to a fixed version: etcd-io etcd 3.3.23, 3.4.10. Check the vendor advisory for mitigations.

References

https://github.com/etcd-io/etcd/security/advisories/GHSA-m332-53r6-2w93
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/L6B6R43Y7M3DCHWK3L3UVGE2K6WWECMP/
https://github.com/etcd-io/etcd/security/advisories/GHSA-m332-53r6-2w93
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/L6B6R43Y7M3DCHWK3L3UVGE2K6WWECMP/

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