How severe is CVE-2021-23347?

CVE-2021-23347 has a CVSS score of 4.8/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance.

Which packages are affected by CVE-2021-23347?

CVE-2021-23347 affects the following packages: github.com/argoproj/argo-cd/v2 (Go), github.com/argoproj/argo-cd/v2 (Go). Ecosystems affected: Go.

How do I fix CVE-2021-23347?

Update github.com/argoproj/argo-cd/v2 to 1.7.13 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-23347 is resolved across your whole dependency graph.

How do I detect CVE-2021-23347 in my Go dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/argoproj/argo-cd/v2, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2021-23347 if there is no patch (or I can't update yet)?

Escape or sanitise the affected output on the server side rather than relying on client-side filtering, and add a Content-Security-Policy that blocks inline script execution so injected markup cannot run even if it reaches the page.

Is CVE-2021-23347 actively exploited in the wild?

No public exploit code has been indexed for CVE-2021-23347 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2021-23347?

CVE-2021-23347 has an EPSS (Exploit Prediction Scoring System) score of 0.6%, placing it in the 47th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2021-23347?

CVE-2021-23347 is classified as Cross-site Scripting (XSS) (CWE-79). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation. This is a high-impact weakness class that often enables remote code execution or data exposure.

When was CVE-2021-23347 published, and has it been updated?

CVE-2021-23347 was published on March 3, 2021 and was last updated on August 7, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🐹

🐹 Go

Not in CISA KEV

MEDIUM severity

CVE-2021-23347 — argo-cd

MEDIUMFix: argoproj/argo-cd#5563

CVE-2021-23347 is a medium-severity (CVSS 4.8) Cross-site Scripting (XSS) vulnerability in github.com/argoproj/argo-cd/v2. A fix is available for github.com/argoproj/argo-cd/v2 — see the affected versions and patch details below.

Possible XSS when using SSO with the CLI in github.com/argoproj/argo-cd/v2

Also known asBIT-argo-cd-2021-23347GHSA-qq5v-f4c3-395cGO-2022-0869SNYK-GOLANG-GITHUBCOMARGOPROJARGOCDCMD-1078291

Published

Mar 3, 2021

Updated

Aug 7, 2026

Affected

2 pkgs

Patched

2 / 2

Exploits

None indexed

Exploitation data as of Oct 10, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

EPSS Exploitation Probability

via FIRST.org ↗

0.6%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs47th percentile — riskier than 47% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

How urgent is this, really

CVE-2021-23347 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.

Where this sits among everything scored

Of 385,386 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.

Real-World Exposure

2 pkgs affected

🐹github.com/argoproj/argo-cd/v2🐹github.com/argoproj/argo-cd/v2

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.

Description

Impact

When using SSO with the Argo CD CLI, a malicious SSO provider could have sent specially crafted error message that would result in XSS on the client by means of executing arbitrary JavaScript code.

We believe the exploitation of this vulnerability is only be possible when Argo CD is connected to a compromised/malicious SSO provider.

Patches

A patch for this vulnerability is available with the v1.8.7 and v1.7.14 releases of Argo CD.

Workarounds

Do not use SSO with the CLI when you don't trust your SSO provider

If you have any questions or comments about this advisory:

Open an issue in the Argo CD issue tracker or discussions
Join us on Slack in channel #argo-cd

Credits

The issue was found during static code scanning with CodeQL and fixed by the Argo CD team. While we believed that a rogue SSO provider would pose a severe threat by itself, we fixed it like a regular bug.

The Argo CD team would like to thank Adam Gold of Snyk (https://snyk.io) for stepping up and classifying this correctly as a security issue and for his help in determining its severity. Also, Snyk kindly reserved and provided the CVE for this vulnerability.

We fully agree with Adam that this bug is a security vulnerability and justifies publishing a SA, to provide our community and users full transparancy.

Affected Packages

2 total 2 fixed

Ecosystem	Package	Vulnerable range	Fix
🐹Go	`github.com/argoproj/argo-cd/v2`	all versions	1.7.13`go get github.com/argoproj/argo-cd/v2@v1.7.13`
🐹Go	`github.com/argoproj/argo-cd/v2`	≥ 1.8.0&&< 1.8.6	1.8.6`go get github.com/argoproj/argo-cd/v2@v1.8.6`

Affected Products

1 product · 2 configurations

Application

argo cdargoproj

≥ 1.8.0 && < 1.8.6

range

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/argoproj/argo-cd/v2, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update github.com/argoproj/argo-cd/v2 to 1.7.13 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-23347 is resolved across your whole dependency graph.
Workarounds
Escape or sanitise the affected output on the server side rather than relying on client-side filtering, and add a Content-Security-Policy that blocks inline script execution so injected markup cannot run even if it reaches the page.

Frequently Asked Questions

### Impact When using SSO with the Argo CD CLI, a malicious SSO provider could have sent specially crafted error message that would result in XSS on the client by means of executing arbitrary JavaScript code. We believe the exploitation of this vulnerability is only be possible when Argo CD is connected to a compromised/malicious SSO provider. ### Patches A patch for this vulnerability is available with the v1.8.7 and v1.7.14 releases of Argo CD. ### Workarounds * Do not use SSO with the CLI when you don't trust your SSO provider If you have any questions or comments about this advisor

O3 Security · Impact-Aware SCA

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Find it across Go, including transitive dependencies.

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CVSS Score

4.8/10CVSS v3 base

Vector breakdown

Attack Vector

Network

Attack Complexity

Low

Privileges Required

High

User Interaction

Required

Scope

Changed

Confidentiality

Low

Integrity

Low

Availability

None

Raw vector

CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N

CWE Classification

CWE-79Cross-site Scripting (XSS)

Weaponization

No known public exploit tooling found.

OpenSSF Scorecard

Package health score

argo-cd

8.9/10

Code-Review10/10

Maintained10/10

Dependency-Update-Tool10/10

Branch-Protection8/10

Vulnerabilities0/10

Assessed Oct 10, 2026

Timeline

Disclosed

Mar 3, 2021

Last updated

Aug 7, 2026

Identifiers

CVE-2021-23347

GHSA-qq5v-f4c3-395c

BIT-argo-cd-2021-23347

GO-2022-0869

SNYK-GOLANG-GITHUBCOMARGOPROJARGOCDCMD-1078291

References

Advisorysnyk.io Advisorynvd.nist.gov Fixgithub.com Webgithub.com

Related vulnerabilities

This CVE is medium severity; 8 of 8 other CVEs affecting v2 are rated as high or higher (top: critical).

CVE-2026-45738CVE-2025-59531CVE-2025-55191CVE-2025-59538CVE-2025-59537CVE-2025-55190CVE-2025-47933CVE-2025-23216

Provenance

Sources

OSV.devNVDFIRST.org (EPSS)

Last verifiedAug 7, 2026