Skip to content

RCE via ZipSlip and symbolic links in argoproj/argo-workflows

High
Joibel published GHSA-xrqc-7xgx-c9vh Dec 9, 2025

Package

gomod github.com/argoproj/argo-workflows (Go)

Affected versions

>=3.7.0, <=3.7.5
<3.6.14

Patched versions

3.7.5
3.6.14

Description

Summary

The patch deployed against CVE-2025-62156 is ineffective against malicious archives containing symbolic links.

Details

The untar code that handles symbolic links in archives is unsafe. Concretely, the computation of the link's target and the subsequent check are flawed:

argo-workflows/workflow/executor/executor.go

Lines 1034 to 1037 in 5291e0b

linkTarget := filepath.Join(filepath.Dir(target), header.Linkname)
if !strings.HasPrefix(filepath.Clean(linkTarget), filepath.Clean(dest)+string(os.PathSeparator)) {
return fmt.Errorf("illegal symlink target: %s -> %s", header.Name, header.Linkname)
}

PoC

  1. Create a malicious archive containing two files: a symbolik link with path "./work/foo" and target "/etc", and a normal text file with path "./work/foo/hostname".
  2. Deploy a workflow like the one in GHSA-p84v-gxvw-73pf with the malicious archive mounted at /work/tmp.
  3. Submit the workflow and wait for its execution.
  4. Connect to the corresponding pod and observe that the file "/etc/hostname" was altered by the untar operation performed on the malicious archive. The attacker can hence alter arbitrary files in this way.

Impact

The attacker can overwrite the file /var/run/argo/argoexec with a script of their choice, which will be executed at the pod's start.

Severity

High

CVSS overall score

This score calculates overall vulnerability severity from 0 to 10 and is based on the Common Vulnerability Scoring System (CVSS).
/ 10

CVSS v3 base metrics

Attack vector
Network
Attack complexity
Low
Privileges required
Low
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
High
Availability
High

CVSS v3 base metrics

Attack vector: More severe the more the remote (logically and physically) an attacker can be in order to exploit the vulnerability.
Attack complexity: More severe for the least complex attacks.
Privileges required: More severe if no privileges are required.
User interaction: More severe when no user interaction is required.
Scope: More severe when a scope change occurs, e.g. one vulnerable component impacts resources in components beyond its security scope.
Confidentiality: More severe when loss of data confidentiality is highest, measuring the level of data access available to an unauthorized user.
Integrity: More severe when loss of data integrity is the highest, measuring the consequence of data modification possible by an unauthorized user.
Availability: More severe when the loss of impacted component availability is highest.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H

CVE ID

CVE-2025-66626

Weaknesses

Relative Path Traversal

The product uses external input to construct a pathname that should be within a restricted directory, but it does not properly neutralize sequences such as .. that can resolve to a location that is outside of that directory. Learn more on MITRE.

Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')

The product constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command when it is sent to a downstream component. Learn more on MITRE.

Credits