How to Evaluate a PDF SDK Vendor's Security Posture

When you embed a PDF SDK in your product, you inherit its security posture. Every vulnerability in the library becomes a vulnerability in your application, and every document your software opens, converts, or redacts passes through code you didn't write.

Security reviewers know this, which is why PDF components increasingly show up in vendor questionnaires and procurement checklists. But "evaluate the vendor's security" is vague advice. This guide breaks it into concrete steps: what to ask for, how to interpret what you get back, and which answers should slow down a purchase.

Not sure where your own setup stands first? Use our PDF Security Compliance Checklist for Enterprise Teams to see where you are doing well and where you may have some gaps in security.

Step 1: Start with what the vendor actually touches

Before you ask for any paperwork, establish the deployment model, because it determines how much of the vendor's security matters to yours.

• An SDK you embed and run in your own environment means documents never leave your infrastructure. The vendor's exposure to your data is minimal, but the code itself is a supply chain dependency, so vulnerability management matters most.
• A hosted API or cloud service means your documents travel to the vendor's servers. Their infrastructure, access controls, data retention, and subprocessors are now part of your risk surface.

Many teams discover mid-evaluation that a product they assumed was a library is actually a service, or that a "local" SDK phones home for licensing or telemetry. Ask early and get the answer in writing. Our guide to on-premises vs. cloud PDF processing covers how that choice affects compliance.

Step 2: Ask for attestations, then actually read them

A security page with certification logos tells you very little. Ask for the underlying documents.

SOC 2 report. Request the full report, which is usually available under NDA, not a summary. When you read it, check:

• Type 1 or Type 2. Type 1 reviews whether controls are designed appropriately at a single point in time. Type 2 reviews whether they operated effectively over a period, usually several months. Type 2 is the stronger evidence.
• Scope. Does the report cover the product and systems you'll depend on, or only part of the company?
• The auditor's opinion and any exceptions. Exceptions aren't automatically disqualifying, but you want to see what they were and how the vendor responded.
• Report period. If the period ended a while ago, ask for a bridge letter covering the gap.
• Complementary user entity controls. These are controls the report assumes you have in place. They tell you what your side of the responsibility looks like.

Other evidence worth requesting:

• An ISO 27001 certificate, including its scope statement
• A summary or letter from a recent third-party penetration test
• A completed standard questionnaire, if the vendor maintains one, or a trust center where documents are published

Be cautious of vendors who can't produce any independent evidence, or who describe internal practices without anyone outside the company verifying them.

Step 3: Probe how they handle vulnerabilities

Every software vendor ships bugs. What separates a safe dependency from a risky one is how quickly and transparently the vendor responds.

Ask:

• Is there a published process for reporting security vulnerabilities, and a named contact?
• How are customers notified of security fixes, and how fast?
• Do they publish security advisories? Can you review the history of past issues?
• What are the patch timelines for critical, high, and medium severity issues?
• How long are older versions supported with security fixes? Are you forced to upgrade major versions to get a patch?
• Do they have a process for vulnerabilities in third-party components they bundle?

A vendor with a history of published advisories and prompt fixes is often safer than one with a spotless record and no disclosure process. Silence isn't the same as security.

Step 3b: Check how they build and ship the software

PDF libraries are complex, often written in memory-unsafe languages, and parse untrusted input by design. That makes secure development practices especially relevant.

• Can they provide a software bill of materials (SBOM) listing third-party and open-source components?
• How do they monitor and update those dependencies?
• Is their code reviewed and tested for security issues, including fuzzing of file parsers?
• Are releases signed, so you can verify what you install?
• How long has the codebase been in production, and how widely is it deployed? Mature, heavily used code has typically had more of its flaws found and fixed.

Step 4: Understand data handling and privacy

Even an embedded SDK can have data implications. Ask directly:

• Does the software make any outbound network calls (licensing checks, telemetry, crash reports)? Can that be disabled?
• Can it run fully offline or in an air-gapped environment?
• If any service is involved, where is data processed and stored, and for how long?
• Who are the subprocessors, and how are changes communicated?
• Will they sign a data processing agreement or, for healthcare, a business associate agreement if the data warrants it?

For regulated workloads, the answers feed directly into your obligations under frameworks like HIPAA and GDPR. Our guide to SOC 2, HIPAA & GDPR and PDF processing explains how those requirements map to document-handling decisions.

Step 5: Review the contract, not just the controls

Strong security practices matter less if the contract doesn't support you when something goes wrong. Have legal review:

• Breach and incident notification: timelines and what the vendor must tell you
• Security commitments: whether the vendor's stated practices are binding or merely marketing
• Audit rights: whether you can request evidence or conduct an assessment
• Liability and indemnification: especially for IP claims and data incidents
• Redistribution terms: critical if you ship the SDK inside software you sell to customers
• Continuity: what happens to support and updates if the vendor is acquired or changes direction

Step 6: Gauge support and long-term stability

Security is an ongoing relationship, not a one-time purchase. Evaluate:

• Support channels and response commitments for security-related issues
• Direct access to engineers who can answer technical security questions
• Customer retention and reputation. Review sites and reference calls with similar-sized customers can reveal how the vendor behaves after the sale.
• Company track record and longevity

Scorecard: what good looks like and what should worry you

A note on open-source libraries

If you're comparing commercial vendors against open-source options, the same questions apply, but there's no vendor to answer them. Someone on your team becomes responsible for tracking advisories, patching, and verifying the supply chain. That's not necessarily a dealbreaker, but it's a cost to include in the comparison.

Running the evaluation efficiently

1. Involve security early. Bring your security team in before you shortlist, not at the end.
2. Send a short, specific request for the SOC 2 report, pen test summary, SBOM, and vulnerability policy. Vendors that respond quickly and completely are usually the ones that take security seriously.
3. Score every vendor with the same table so the comparison is consistent.
4. Verify one or two claims independently, such as reviewing the advisory history or speaking with a reference customer.

Next steps

Datalogics is SOC 2 Type 2 compliant and publishes security documentation through its Trust Center at trust.datalogics.com. If your security team is running a vendor review, Contact Us and we'll help you get the answers your reviewers need.

This guide is general information, not legal advice. Evaluation criteria and contract terms vary by organization and industry, so involve your security, legal, and procurement teams.