dbcve.org
Deserialization of Untrusted DataWeakness · CWE-502

CVE-2025-62515

CRITICAL · 9.8 CVSS v3.1 Published 2025-10-17
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
100/100
Remediation priority · Urgent
Remotely reachable No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
pyquokka is a framework for making data lakes work for time series. In versions 0.3.1 and prior, the FlightServer class directly uses pickle.loads() to deserialize action bodies received from Flight clients without any sanitization or validation in the do_action() method. The vulnerable code is located in pyquokka/flight.py at line 283 where arbitrary data from Flight clients is directly passed to pickle.loads(). When FlightServer is configured to listen on 0.0.0.0, this allows attackers across the entire network to perform arbitrary remote code execution by sending malicious pickled payloads through the set_configs action. Additional vulnerability points exist in the cache_garbage_collect, do_put, and do_get functions where pickle.loads is used to deserialize untrusted remote data.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

pyquokka's FlightServer uses pickle.loads() to deserialize untrusted data from Flight clients in multiple locations (do_action, cache_garbage_collect, do_put, do_get) without any validation. When the server binds to 0.0.0.0, remote attackers can send malicious pickled payloads to achieve arbitrary remote code execution.

MitigationReplace pickle.loads() with safe deserialization (e.g., JSON, or restrict pickle to trusted/validated sources) and ensure FlightServer binds to localhost only or implement proper authentication/authorization.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Confirm pyquokka installation
    Run 'pip show pyquokka' or check your Python environment for the pyquokka package
    Affected if pyquokka is installed and the version is within the affected range (if known)
  2. Identify FlightServer usage
    Search your codebase for imports of pyquokka FlightServer or look for 'from pyquokka import FlightServer' or similar patterns in your application code
    Affected if your application imports and uses pyquokka's FlightServer
  3. Check FlightServer binding address
    Review your application configuration or code where FlightServer is instantiated and look for the host parameter (e.g., server = FlightServer(host='0.0.0.0', ...))
    Affected if FlightServer is configured to bind to 0.0.0.0 instead of localhost or 127.0.0.1
  4. Verify network exposure
    Check if the FlightServer port (typically 8815 or as configured) is exposed to untrusted networks by running 'netstat -tlnp | grep <port>' or reviewing firewall rules
    Affected if The FlightServer port is accessible from network interfaces other than localhost
  5. Inspect pickle deserialization in Flight methods
    Review the pyquokka source code in your environment (typically in site-packages/pyquokka) for pickle.loads() calls within do_action, cache_garbage_collect, do_put, and do_get methods
    Affected if These methods use pickle.loads() to deserialize data from clients without validation

Your environment is affected if pyquokka with FlightServer is installed, the server binds to 0.0.0.0 (network-exposed), and the vulnerable pickle deserialization methods are accessible to untrusted clients.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Replace pickle.loads() with safe deserialization (e.g., JSON, or restrict pickle to trusted/validated sources) and ensure FlightServer binds to localhost only or implement proper authentication/authorization.

Recommended fix Moderate confidence
  1. Replace pickle.loads() with a safe deserialization method (such as json.loads or msgpack) in pyquokka/flight.py at the vulnerable points: do_action() around line 283, cache_garbage_collect, do_put, and do_get functions.
  2. Ensure all action bodies, cache data, and stream data from Flight clients are validated before deserialization.
  3. If pickle deserialization is absolutely required, implement a custom unpickler that whitelists allowed classes using the `AllowedTypes` module or similar allowlist mechanism.
  4. Restart the FlightServer service after applying the patch.
  5. Test the patched implementation by attempting to send known malicious pickle payloads to verify they are rejected.

Generated from the published advisory — verify against the referenced sources before acting.

Have this fixed Scoped from the published advisory
  • Consultation6.0 h
  • Implementation12.0 h
  • Testing6.0 h
  • Review / QA4.0 h
28.0 hours of engineering $4,980
Get help mitigating

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $7,968.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2025-62515 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

Get it on GitHub Scan in the browser

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2025-62515 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data