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🐍 PyPI

GHSA-q34h-97wf-8r8j

HIGH

vault-cli contains possible RCE when reading user-defined data

Also known asCVE-2021-43837PYSEC-2021-853
Published
Dec 16, 2021
Updated
Mar 13, 2026
Affected
1 pkg
Patched
1 / 1
Exploits
2 known

EPSS Exploitation Probability

via FIRST.org ↗
5.0%probability of exploitation in next 30 days
Lower Risk91th percentile-2.47%
3.64%6.06%8.49%10.9%9.6%5.0%Dec 25Apr 26Jun 26

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

Blast Radius

1 pkg affected
🐍vault-cli

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.

Description

Impact

What kind of vulnerability is it? Who is impacted?

vault-cli features the ability for rendering templated values (as explained in the documentation). When a secret starts with the prefix !template!, vault-cli interprets the rest of the contents of the secret as a Jinja2 template. Jinja2 is a powerful templating engine and it's not designed to safely render arbitrary templates. An attacker controlling a jinja2 template rendered on a machine can trigger arbitrary code, making this a Remote Code Execution (RCE) risk. If the content of the vault can be completely trusted, then this is not a problem. Otherwise, if your threat model includes cases where an attacker can manipulate a secret value read from the vault using vault-cli, then this vulnerability may impact you.

This does not impact vault itself, except for the fact that the attacker, having an RCE on the machine that executes vault-cli, may abuse the token that vault-cli uses, to read, write or delete other data from the vault.

Patches

Has the problem been patched? What versions should users upgrade to?

In 3.0.0, the code related to interpreting vault templated secrets has been removed entirely.

Workarounds

Is there a way for users to fix or remediate the vulnerability without upgrading?

Using the environment variable VAULT_CLI_RENDER=false or the flag --no-render (placed between vault-cli and the subcommand, e.g. vault-cli --no-render get-all) or adding render: false to the vault-cli configuration yaml file disables rendering and removes the vulnerability. Using the python library, you can use: vault_cli.get_client(render=False) when creating your client to get a client that will not render templated secrets and thus operates securely.

References

Are there any links users can visit to find out more?

Here's an article explaining how jinja2 templates might be exploited to have side effects: https://podalirius.net/en/publications/grehack-2021-optimizing-ssti-payloads-for-jinja2/

For more information

If you have any questions or comments about this advisory:

Affected Packages

1 total 1 fixed
EcosystemPackageVulnerable rangeFix
🐍PyPIvault-cli0.7.0&&< 3.0.03.0.0
Exploits & PoCs
2

Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.

Detection & mitigation playbook

Open-source dependency
  1. Detect

    Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for vault-cli. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.

  2. Fix

    Update vault-cli to 3.0.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-q34h-97wf-8r8j is resolved across your whole dependency graph.

  3. Workarounds

    If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

  4. How O3 protects you

    O3 pinpoints whether GHSA-q34h-97wf-8r8j is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Tailored to GHSA-q34h-97wf-8r8j. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

### Impact _What kind of vulnerability is it? Who is impacted?_ vault-cli features the ability for rendering templated values (as explained in the [documentation](https://github.com/peopledoc/vault-cli/blob/2.2.1/docs/howto/templated_secrets.rst)). When a secret starts with the prefix `!template!`, vault-cli interprets the rest of the contents of the secret as a Jinja2 template. Jinja2 is a powerful templating engine and it's not designed to safely render arbitrary templates. An attacker controlling a jinja2 template rendered on a machine can trigger arbitrary code, making this a Remote Code
O3 Security · Impact-Aware SCA

Is GHSA-q34h-97wf-8r8j in your dependencies?

O3 detects GHSA-q34h-97wf-8r8j across PyPI dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.