dbcve.org
FedoraOperating system · Fedoraproject

CVE-2019-10906

HIGH · 8.6 CVSS v3.1 Published 2019-04-07
Fix available
A fix is available. Upgrade to 2.10.1 or later.
See remediation →
95/100
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
In Pallets Jinja before 2.10.1, str.format_map allows a sandbox escape.

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

In Pallets Jinja2 before version 2.10.1, the str.format_map method can be exploited to escape the template sandbox and access underlying Python objects, potentially allowing arbitrary code execution or information disclosure.

MitigationUpgrade Jinja2 to version 2.10.1 or later. If immediate upgrade is not possible, disable untrusted template input or implement additional input validation.

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

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
FedoraOperating system
Affected:= 28= 29= 30
Ubuntu LinuxOperating system
Affected:= 12.04= 14.04= 16.04= 18.04= 18.10= 19.04
Software CollectionsApplication
Affected:= 1.0
JinjaApplication
Affected:< 2.10.1
LeapOperating system
Affected:= 15.0= 42.3

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
Changed
Confidentiality
High
Integrity
None
Availability
None

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

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. Check installed Jinja2 version
    Run `pip show jinja2` or check your package manager (e.g., `rpm -q python-jinja2`, `dpkg -l python-jinja2`) to identify the installed version number
    Affected if The version is lower than 2.10.1
  2. Identify if templates process untrusted user input
    Review your application code to determine whether Jinja2 templates are being rendered with data that originates from external or untrusted sources (e.g., user form submissions, API inputs, external APIs)
    Affected if Untrusted input is directly passed to template rendering without sanitization
  3. Verify if the Jinja2 sandbox is enabled
    Search your codebase for `SandboxedEnvironment` usage. Check if templates are loaded via `Environment(loader=...).get_template()` or if `sandbox.SandboxedEnvironment` is explicitly used
    Affected if The sandbox is being relied upon for security and the Jinja2 version is below 2.10.1
  4. Confirm str.format_map usage in templates
    Search your template files for the pattern `{0.format_map}` or similar, which invokes the vulnerable str.format_map method within template expressions
    Affected if Templates contain str.format_map calls and Jinja2 is below version 2.10.1

You are affected if Jinja2 version is below 2.10.1 and your application renders templates with untrusted input while relying on the sandbox for security.

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.

From vendor data
Upgrade available Upgrade to 2.10.1 or later
Fixed in 2.10.1
Interim mitigation

Upgrade Jinja2 to version 2.10.1 or later. If immediate upgrade is not possible, disable untrusted template input or implement additional input validation.

Fix this in Fedora Scoped from the published advisory
  • Consultation3.0 h
  • Implementation2.0 h
  • Testing4.0 h
  • Review / QA2.0 h
11.0 hours of engineering $1,920
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $3,072.

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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-2019-10906 in production — separate from our analysis above.

No notes yet

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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