CVE-2021-41803: HashiCorp Consul 1.8.1 up to 1.11.8, 1.12.4, and 1.13.1 do not properly validate the node or segment names pri

This month

HIGH 7.1UPGRADE

CVE-2021-41803 is a high-severity flaw (CVSS 7.1) affecting consul. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

HashiCorp Consul 1.8.1 up to 1.11.8, 1.12.4, and 1.13.1 do not properly validate the node or segment names prior to interpolation and usage in JWT claim assertions with the auto config RPC. Fixed in 1.11.9, 1.12.5, and 1.13.2."

Why this priority

High severity

A fixed release or distro patch exists.

Risk facts

CVSS score	7.1 (High)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	Low
User interaction	None
EPSS exploit chance	1.1% (top 35%)
CISA exploited list	No
Weakness	CWE-862
Published	2022-09-23
Last modified	2026-06-17

Publisher (CNA): MITRE · Vendor: hashicorp

Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2022-09-23 01:15 UTCPublished CVE record published
2026-06-17 04:08 UTCUpdated Record last modified

hashicorp consul UPGRADE

Affected: >= 1.8.1 and < 1.11.9 · 1.12.4 · 1.13.1

Fixed in: 1.11.9

Safe to downgrade to: a release before 1.8.1

1. Check installed version

apt-cache policy consul || rpm -q consul || consul --version

2. UPGRADE to 1.11.9 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade consul

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade consul

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

3. If no update is available yet, DOWNGRADE to a release before 1.8.1 (Debian / Ubuntu)

apt-cache madison consul sudo apt install consul=<VERSION_BEFORE_1.8.1> sudo apt-mark hold consul

3. If no update is available yet, DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list consul sudo dnf downgrade consul-<VERSION_BEFORE_1.8.1> sudo dnf versionlock add consul

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2021-41803?

consul: upgrade to 1.11.9. Exact commands for each OS are on this page.

Is CVE-2021-41803 being exploited?

CVE-2021-41803 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2021-41803 affect?

CVE-2021-41803 affects consul. Severity is high (CVSS 7.1). HashiCorp Consul 1.8.1 up to 1.11.8, 1.12.4, and 1.13.1 do not properly validate the node or segment names prior to interpolation and usage in JWT claim assertions with the auto config RPC. Fixed in 1.11.9, 1.12.5, and 1.13.2."

How urgent is CVE-2021-41803?

Priority 41/100. High severity

Software pages

Consul vulnerabilities

Related CVEs

CVE-2025-11374 MEDIUM 6.5 UPGRADE Consul and Consul Enterprise’s (“Consul”) key/value endpoint is vulnerable to denial of service (DoS) due to i
CVE-2025-11375 MEDIUM 6.5 UPGRADE Consul and Consul Enterprise’s (“Consul”) event endpoint is vulnerable to denial of service (DoS) due to lack
CVE-2024-10086 MEDIUM 6.1 UPGRADE A vulnerability was identified in Consul and Consul Enterprise such that the server response did not explicitl
CVE-2024-10006 HIGH 8.3 UPGRADE A vulnerability was identified in Consul and Consul Enterprise (“Consul”) such that using Headers in L7 traffi
CVE-2024-10005 HIGH 8.1 UPGRADE A vulnerability was identified in Consul and Consul Enterprise (“Consul”) such that using URL paths in L7 traf

References

← Back to latest CVEs