Scapy Session Loading Vulnerable to Arbitrary Code Execution via Untrusted Pickle Deserialization

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS 4.0

5.4 · CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N · score source

EPSS

No dated EPSS signal available.

As published by the source; long descriptions are shortened.

Summary An unsafe deserialization vulnerability in Scapy <v2.7.0 allows attackers to execute arbitrary code when a malicious session file is locally loaded via the -s option. This requires convincing a user to manually load a malicious session file. --- Details Scapy’s interactive shell supports session loading using gzip-compressed pickle files: Internally, this triggers: Since no validation or restriction is performed on the deserialized object, any code embedded via reduce() will be executed immediately. This makes it trivial for an attacker to drop a malicious .pkl.gz in a shared folder and have it executed by unsuspecting users. The vulnerability exists in the loadsession function, which deserializes data using pickle.load() on .pkl.gz files provided via the -s CLI flag or programmatically through conf.session. Affected lines in source code: https://github.com/secdev/scapy/blob/master/scapy/main.py#L569-L572 Impact This is a classic deserialization vulnerability which leads to…

Published by the source

22 Oct 2025, 16:45 UTC

Last modified by the source

23 Oct 2025, 20:17 UTC

Source last checked

26 Oct 2026, 13:35 UTC

1. Revision 3 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-cq46-m9x9-j8w2

2. Revision 2 · amended · 24 Oct 2026

   Reviewed OSV alias/range/CVSS4 correction; package source scopes and original publication preserved. No customer finding resolved.

3. Revision 1 · created · 24 Oct 2026

   Published from osv record GHSA-cq46-m9x9-j8w2

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# Patch Next advisory brief: GHSA-cq46-m9x9-j8w2

Advisory: Scapy Session Loading Vulnerable to Arbitrary Code Execution via Untrusted Pickle Deserialization
IDs: GHSA-cq46-m9x9-j8w2
Record: https://patchnext.com/advisories/ghsa-cq46-m9x9-j8w2 (revision 3, source checked 26 Oct 2026, 13:35 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 5.4)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor response not established. A vendor fix does not mean a deployment is fixed.

## Affected components
- PyPI scapy: affected <= 2.6.1

## Suggested inspection (read-only)
- `python -m pip show scapy`: prints the installed version. Run with the environment that serves production active.

## Supported action
No complete vendor fix is recorded. Follow the primary source's mitigation guidance and check this record again before closing anything.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on scapy.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://osv.dev/vulnerability/GHSA-cq46-m9x9-j8w2 (OSV record GHSA-cq46-m9x9-j8w2 lists affected ranges: PyPI scapy >=0 <=2.6.1)
- Verified: https://github.com/advisories/GHSA-cq46-m9x9-j8w2 (GitHub-reviewed advisory GHSA-cq46-m9x9-j8w2 lists affected ranges: PyPI scapy >=0 <=2.6.1)

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