CVE-2021-37914Public exploitNetwork attack vector

Workflow rewriting via re-evaluated expression output

Published Aug 2, 2021 · Updated Aug 4, 2024

Input validation failure in Argo Workflows 3.1.0 through 3.1.5 allows attackers to rewrite running workflows through crafted parameters. The controller inserts expression-template output into a JSON-stringified template and evaluates it again, letting injected duplicate keys replace fields such as container arguments. The flaw is reachable only when expression templates are enabled and untrusted users can supply workflow input parameters; successful rewriting disrupts or alters workflow execution.

CVSS severity6.5
Medium
EPSS probability0.96%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Input validation failure in Argo Workflows 3.1.0 through 3.1.5 allows attackers to rewrite running workflows through crafted parameters. The controller inserts expression-template output into a JSON-stringified template and evaluates it again, letting injected duplicate keys replace fields such as container arguments. The flaw is reachable only when expression templates are enabled and untrusted users can supply workflow input parameters; successful rewriting disrupts or alters workflow execution.

The record

CVE
CVE-2021-37914
Published
Aug 2, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-20, T1565.001
Attack vector
network
Privileges
Unavailable

Timeline

How it unfolded

  1. Aug 2, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesUnavailable in this record.

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

5.8NIST NVDAV:N/AC:M/Au:N/C:N/I:P/A:P
6.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
PrivilegesUnavailable
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-20Improper Input Validation
T1565.001Stored Data Manipulation

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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