CVE-2020-15106 | Improper Input Validation in etcd

In etcd before versions 3.3.23 and 3.4.10, a large slice causes panic in decodeRecord method. The size of a record is stored in the length field of a WAL file and no additional validation is done on this data. Therefore, it is possible to forge an extremely large frame size that can unintentionally panic at the expense of any RAFT participant trying to decode the WAL.

Published: 2020-08-05 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2020-15106 is rated Moderate Risk (50.4/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 1.29%). EPSS rose +1.18% over the last day, indicating growing attacker interest. Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2020-15106

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.11% 1.29% +1.18%
2 2025-11-21 0.30% 0.11% -0.19%
3 2025-11-18 — 0.30% —

Full EPSS history (10 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2020-15106

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.5 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 2.8 3.6 [email protected]
6.5 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 2.8 3.6 [email protected]
4.0 2.0 MEDIUM
AV:N/AC:L/Au:S/C:N/I:N/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:S)
A single authentication is required.
Confidentiality impact (C:N)
No confidentiality impact.
Integrity impact (I:N)
No integrity impact.
Availability impact (A:P)
Partial availability impact.
 8.0 2.9 [email protected]

Weakness enumeration for CVE-2020-15106

GitHub Security Advisory for CVE-2020-15106

GHSA-p4g4-wgrh-qrg2 · Severity: low · Ecosystem: go — Panic due to malformed WALs in go.etcd.io/etcd

OS Trackers for CVE-2020-15106

vendor priority summary link
debian not yet assigned CVE-2020-15106 not yet assigned priority: Debian including 1 source packages (etcd), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2020-15106
redhat medium — https://access.redhat.com/security/cve/CVE-2020-15106
suse medium CVE-2020-15106 severity moderate: SUSE including 44 source package names (1.17.17:kubernetes-client-1.17.13-4.21.2, 1.17.17:kubernetes-common-1.17.13-4.21.2, …), 53 product×package rows across 16 product lines (Container caasp/v4/coredns, Container caasp/v4/etcd, … (16 product lines)): Fixed 53. https://www.suse.com/security/cve/CVE-2020-15106/
ubuntu medium CVE-2020-15106 medium priority: Ubuntu including 1 source packages (etcd), 16 status rows across 16 suites (bionic, focal, groovy, hirsute, impish, jammy, kinetic, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): ignored 8, needed 4, released 3, DNE 1. https://ubuntu.com/security/CVE-2020-15106

Affected software / configurations for CVE-2020-15106

Vendor Product Version Raw CPE
etcd etcd < 3.3.23 cpe:2.3:a:etcd:etcd:*:*:*:*:*:*:*:*
etcd etcd >= 3.4.0, < 3.4.10 cpe:2.3:a:etcd:etcd:*:*:*:*:*:*:*:*
fedoraproject fedora 32 cpe:2.3:o:fedoraproject:fedora:32:*:*:*:*:*:*:*

References for CVE-2020-15106

cvelogic Threat Intelligence