CriticalCVE-2026-42880

ArgoCD ServerSideDiff is vulnerable to Kubernetes Secret Extraction (CVE-2026-42880)

Published 07.05.2026Last modified 26.10.2026Sources: Red Hat, BSI, CVE.org, OSV, EUVD

Public exploit

What is affected, what to do

Argo CD is a declarative, GitOps continuous delivery tool for Kubernetes. From versions 3.2.0 to before 3.2.11 and 3.3.0 to before 3.3.9, there is a missing authorization and data-masking gap in Argo CD's ServerSideDiff endpoint that allows an attacker with read-only access to extract plaintext Kubernetes Secret data from etcd via the Kubernetes API server's Server-Side Apply dry-run mechanism.

An exploit is publicly available. Update argo_cd to version 3.3.9, Argo CD to version 3.3.9, github.com/argoproj/argo-cd/v3 to version 3.2.11.

Affected: Argo-cd gte 3.2.0, < 3.2.11..*

Not sure whether and how you are affected? Ask a question about this vulnerability

Metrics

9.6

Priority

XIEM Effective CVSS: highest available CVSS rating from NVD and vendor data.

Source: NVD, CVSS v3

9.6

CVSS v3

Severity Critical on the scale from 0 to 10.

Source: Red Hat, BSI, CVE.org, OSV, EUVD

0.7 %

EPSS score

Low — model estimates < 1% exploitation likelihood.

Source: FIRST EPSS, percentile 50.6

Show all metrics

Severity: Critical
Priority (0–325) The priority score is a consolidated metric that condenses several individual signals into a single, action-guiding ranking: technical severity (CVSS), exploitation likelihood (EPSS), known-exploited status (KEV) and the context of the affected asset. The aim is to answer the only truly important question in vulnerability management: what first? Read in glossary: 85.74 Methodology
Exploit maturity An exploit is code or a technique that specifically uses a concrete vulnerability to force unintended behaviour — such as executing code or escalating privileges. It is the tool that turns a theoretical flaw into a practical attack. Read in glossary: PoC (publicly reported)
XIEM Effective CVSS XIEM® is the tiered managed-security operating model from NEOSEC and a registered trademark of NEOSEC GmbH. It extends classic SIEM — the central collection, normalisation and correlation of security-relevant events — with endpoint forensics, network visibility and deception technology, and consolidates them into three building tiers: Sentry, Orchestrate and Command. Read in glossary: 9.6 Methodology
CVSS v3 CVSS is the globally established, open standard for assessing the technical severity of a vulnerability on a scale from 0 to 10. It describes how easily a flaw can be exploited and what damage it can cause — but not how likely its actual exploitation is. CVSS and the complementary EPSS deliberately answer different questions. Read in glossary: 9.6
EPSS score The EPSS score is the absolute model output for an individual vulnerability: the estimated probability of real-world exploitation within the next 30 days, expressed as a value between 0 and 1 (i.e. 0 % to 100 %). A score of 0.42 means „the model estimates a 42 % chance of real-world exploitation within 30 days“. Read in glossary: 0.7 %; Low — model estimates < 1% exploitation likelihood.
EPSS percentile The EPSS percentile is the relative position of a vulnerability within all EPSS-scored CVEs, expressed as a value between 0 and 1. A percentile of 0.90 means „this CVE has a higher EPSS score than 90 % of all other scored CVEs“. Unlike the EPSS score, it is not a probability — but a positioning within a ranking. Read in glossary: 50.6; High — this CVE ranks above the median of all CVEs scored today (rank ≥ 36%).
KEV status The KEV catalogue is a list maintained by the US authority CISA of vulnerabilities for which active exploitation in the wild has been confirmed. It answers not the question „how severe?“ but „is it already being attacked?“ — thereby sharply prioritising patching. Read in glossary: —
Published: 07.05.2026
CWE CWE is a catalogue of typical weakness types in software and hardware — such as flawed input validation, unsafe memory handling or poor authentication. Where a CVE names a concrete vulnerability in a concrete product, a CWE describes the underlying class of defect. Read in glossary: CWE-200, CWE-212, CWE-201

Detection rules

No NEOSEC detection rule is available for this vulnerability yet.

Classification under NIS2 and CRA

Rule-based classification from exploitation status and severity. It does not replace a case-by-case assessment.

NIS2 NIS2 is EU Directive (EU) 2022/2555 to raise the level of cybersecurity across the Union. It substantially broadens obligations compared with the first NIS directive: more sectors, mandatory risk management, staged reporting duties and personal accountability of senior management. Read in glossary: High technical severity: assess and remediate the vulnerability in vulnerability handling under Art. 21(2)(e) NIS2 and document the decision.
CRA The CRA is EU Regulation (EU) 2024/2847 setting horizontal cybersecurity requirements for „products with digital elements“ — from industrial controllers and software to connected consumer devices. For the first time manufacturers must ensure security across the entire product lifecycle, handle vulnerabilities and provide security updates. Read in glossary: From 11.12.2027, Annex I Part II CRA requires manufacturers of affected products with digital elements to handle vulnerabilities without delay and provide security updates.
ISO/IEC 27001 ISO/IEC 27001 is the internationally leading standard for an information security management system (ISMS). It describes a risk-based, process-oriented framework to systematically plan, implement, review and improve information security. Read in glossary: Control A.8.8, management of technical vulnerabilities: assess relevance to your systems, plan remediation and keep evidence.

Description

Source: redhat_csaf, BSI CSAF, BSI WID Portal, NVD (NIST), OSV (Open Source Vulnerabilities), cvelistv5, CVE.org (MITRE), ENISA EUVD

Affected products

The following versions are affected. Older releases of the same product line are also vulnerable unless stated otherwise.

Affected products
		Affected versions	Fixed in
argoproj	argo-cd	`≥ 3.2.0, < 3.2.11`	—
argoproj	argo_cd	`3.3.0 – < 3.3.9` `3.2.0 – < 3.2.11`	`3.3.9` `3.2.11`
Open Source	Argo CD	`< 3.3.9` `< 3.2.11`	`3.3.9` `3.2.11`
go	github.com/argoproj/argo-cd/v3	`3.2.0` `3.3.0`	`3.2.11` `3.3.9`

Vendors and products

Weakness classes (CWE)

CWE-200Exposure of Sensitive Information to an Unauthorized Actor
Class
The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information.
Entry at MITRE CWE-200
CWE-212Improper Removal of Sensitive Information Before Storage or Transfer
Base
The product stores, transfers, or shares a resource that contains sensitive information, but it does not properly remove that information before the product makes the resource available to unauthorized actors.
Entry at MITRE CWE-212
CWE-201Insertion of Sensitive Information Into Sent Data
Base
The code transmits data to another actor, but a portion of the data includes sensitive information that should not be accessible to that actor.
Entry at MITRE CWE-201

Public exploit references

Publicly reported proof-of-concepts, exploit modules and detection templates for this vulnerability. NEOSEC links to the original sources only and does not provide any exploit code.

Public exploit references

Reference tagged as exploit	github.com (opens in a new tab)	PoC (publicly reported)reported, not verified	—

References & sources

security.access.redhat.comdata/csaf/v2/vex/2026/cve-2026-43824.jsonweb
access.redhat.comsecurity/cve/CVE-2026-43824advisory
github.comCVEProject/cvelistV5/tree/main/cves/2026/43xxx/CVE-2026-43824.j…advisory
github.comargoproj/argo-cd/security/advisories/GHSA-3v3m-wc6v-x4x3advisory, x_refsource_CONFIRM, web, Exploit, Vendor advisory
NVD (NIST)vuln/detail/CVE-2026-43824advisory
bugzilla.redhat.comshow_bug.cgi?id=2464613report
access.redhat.comsecurity/cve/CVE-2026-42880Vulnerability database, x_refsource_REDHAT
bugzilla.redhat.comRHBZ#2467882Issue tracking, x_refsource_REDHAT
security.access.redhat.comdata/csaf/v2/vex/2026/cve-2026-42880.jsonx_sadp-csaf-vex
access.redhat.comerrata/RHSA-2026:20943Vendor advisory, x_refsource_REDHAT
access.redhat.comerrata/RHSA-2026:20947Vendor advisory, x_refsource_REDHAT
access.redhat.comerrata/RHBA-2026:12433Vendor advisory, x_refsource_REDHAT
NVD (NIST)vuln/detail/CVE-2026-42880web, advisory
github.comargoproj/argo-cdpackage

Changes to this CVE

Who changed this CVE and when: NVD (analysis, affected products, CVSS), the CVE publisher (CNA) and additional providers such as CISA (ADP).

07.09.2026Record modifiedGitHub

New references:

https://github.com/argoproj/argo-cd/security/advisories/GHSA-3v3m-wc6v-x4x3

Show 3 original changes

Individual changes of this event as published by NVD
Type	Action	Before	After
Reference	added	—	https://github.com/argoproj/argo-cd/security/advisories/GHSA-3v3m-wc6v-x4x3
Reference	removed	https://github.com/argoproj/argo-cd/security/advisories/GHSA-3v3m-wc6v-x4x3	—
Reference type	removed	https://github.com/argoproj/argo-cd/security/advisories/GHSA-3v3m-wc6v-x4x3 Types: Exploit, Vendor Advisory	—

Source identifier: security-advisories@github.com

07.09.2026Record modifiedCISA ADP

New references:

https://github.com/argoproj/argo-cd/security/advisories/GHSA-3v3m-wc6v-x4x3

Show 3 original changes

Individual changes of this event as published by NVD
Type	Action	Before	After
Reference	added	—	https://github.com/argoproj/argo-cd/security/advisories/GHSA-3v3m-wc6v-x4x3
Reference	removed	https://github.com/argoproj/argo-cd/security/advisories/GHSA-3v3m-wc6v-x4x3	—
Reference type	removed	https://github.com/argoproj/argo-cd/security/advisories/GHSA-3v3m-wc6v-x4x3 Types: Exploit, Vendor Advisory	—

Source identifier: 134c704f-9b21-4f2e-91b3-4a467353bcc0

07.09.2026Record modifiedRed Hat ADP

New references:

and 2 more references

Show 13 original changes

Individual changes of this event as published by NVD
Type	Action	Before	After
Affected versions (publisher)	added	—	Affected value modified. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/42xxx/CVE-2026-42880.json">CVE-2026-42880</a>
Reference	added	—	https://access.redhat.com/errata/RHBA-2026:12433
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:20943
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:20947
Reference	added	—	https://access.redhat.com/security/cve/CVE-2026-42880
Reference	added	—	https://bugzilla.redhat.com/show_bug.cgi?id=2467882
Reference	added	—	https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-42880.json
Reference	removed	https://access.redhat.com/errata/RHBA-2026:12433	—
Reference	removed	https://access.redhat.com/errata/RHSA-2026:20943	—
Reference	removed	https://access.redhat.com/errata/RHSA-2026:20947	—
Reference	removed	https://access.redhat.com/security/cve/CVE-2026-42880	—
Reference	removed	https://bugzilla.redhat.com/show_bug.cgi?id=2467882	—
Reference	removed	https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-42880.json	—