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Symantec 2017

Too Big to Fail?

One-third of the internet's certificates. Years of compliance failures. A $950M fire sale.

2017Mass Mis-issuanceSold to DigiCertGradual Distrust
2017 Case Study20 min read
Symantec 2017: Too Big to Fail? - 30% of internet certificates, 18 months forced transformation

Quick Facts

CASymantec (+ VeriSign, Thawte, GeoTrust, RapidSSL)
Year2015-2017
Problem TypePartner oversight failures, mis-issuance at scale
Market Share~30% of all HTTPS certificates
Problematic Certificates30,000+ mis-issued certificates
Time to Full Distrust~3 years (gradual process)
OutcomeSold to DigiCert for ~$950M
The LessonNo CA is "too big to fail." Size doesn't equal competence.

The 30-Second Version

What: Symantec and its brands (VeriSign, Thawte, GeoTrust, RapidSSL) mis-issued tens of thousands of certificates over multiple years, including unauthorized test certificates for Google domains.
When: Issues discovered 2015, announced 2017, full distrust October 2018
Who was hurt: One-third of HTTPS websites had to replace certificates
Why it matters: Proved no CA is "too big to fail." Even the market leader can be distrusted.

The Scale

This wasn't a small CA. Symantec's certificate business included:

BrandMarket Position
SymantecThe parent brand
VeriSignThe original internet CA
ThawteMajor commercial CA
GeoTrustEnterprise-focused
RapidSSLBudget option
EquifaxLegacy brand

~30%

of all HTTPS certificates on the internet

"Norton Secured"

If you saw this seal, that was Symantec

The 2015 Incident: Test Certificates Gone Wrong

September 2015

Google's Certificate Transparency logs caught something alarming.

Symantec's Thawte brand had issued Extended Validation (EV) certificates for domains Symantec didn't own - including google.com and www.google.com.

Symantec's Response

  • "They were just test certificates"
  • "They were never used in the wild"
  • "It was only a few"

The Reality

187

test certificates for domains Symantec didn't own

2,458

certificates for unregistered domains

EV

highest trust level, no validation

Google's Response

Required Symantec to submit ALL certificates to Certificate Transparency logs starting June 2016.

This should have been the end of the story. It wasn't.

The 2017 Discovery: 30,000 More Problems

January 2017

Security researcher Andrew Ayer found more suspicious Symantec certificates in CT logs.

What Google's Investigation Revealed

Symantec had outsourced certificate validation to "Registration Authority" (RA) partners:

CrossCert

Korea

Certisign

Brazil

Certsuperior

Mexico

Certisur

Argentina

These partners could issue certificates under Symantec's root - and Symantec wasn't properly auditing them.

The Numbers

  • At least 30,000 certificates with validation problems
  • Partners issuing EV certificates without EV audits
  • Years of improper oversight
  • No technical controls preventing partner abuse

Symantec's Defense

"Google's claim that we have mis-issued 30,000 SSL/TLS certificates is not true. In the event Google is referring to, 127 certificates – not 30,000 – were identified as mis-issued."

Google counted certificates that violated requirements. Symantec only counted the most egregious cases.

The Pattern of Problems

Mozilla compiled 17 distinct issues with Symantec's CA operations:

IssueDescription
Test certificatesEV certs for google.com, etc.
RA oversight failuresPartners issuing without proper audits
SHA-1 violationsIssued after deprecation date
Failed validationCerts without domain control proof
Audit gapsMissing or invalid audits for sub-CAs
Physical securityRecords not maintained properly
Access controlUnauthorized issuance capability
GeoRoot issuesSub-CAs with compliance problems

The Core Problem

Symantec was operating a massive certificate business without adequate controls. They'd grown through acquisition (VeriSign, Thawte, GeoTrust) and never properly integrated the security practices.

The Browser Response: Gradual Distrust

Google had a problem: immediately distrusting Symantec would break one-third of the internet.

The Solution: Phased Distrust

Chrome VersionDateAction
Chrome 66April 2018Distrust certs issued before June 1, 2016
Chrome 70October 2018Distrust ALL Symantec infrastructure certs

Additional Requirements

  • Maximum certificate validity reduced to 9 months
  • All certificates must be re-validated
  • Symantec must rebuild infrastructure under "Managed CA" partnership

The Fire Sale

July 2017

Facing the destruction of their certificate business, Symantec made a deal.

DigiCert acquired Symantec's CA business for

~$950 Million

The Arrangement

  • DigiCert would operate the Symantec, VeriSign, Thawte, GeoTrust, and RapidSSL brands
  • New certificates would be issued from DigiCert infrastructure
  • Symantec customers could continue using the brand names
  • Old certificates would still need replacement before Chrome 70

Why DigiCert?

DigiCert had a clean reputation and the technical infrastructure to absorb Symantec's massive customer base. They became the world's largest CA overnight.

The Timeline

DateEvent
Sep 2015Google discovers test certs for google.com
Oct 2015Symantec admits to 187 unauthorized test certs
Jun 2016Symantec required to use Certificate Transparency
Jan 2017Andrew Ayer finds more suspicious certificates
Mar 2017Google proposes gradual distrust
Mar 2017Symantec calls proposal "irresponsible"
Apr 2017Mozilla identifies 17 issues
Jul 2017DigiCert acquires Symantec CA for ~$950M
Sep 2017Google finalizes distrust plan
Dec 1, 2017DigiCert begins issuing for Symantec brands
Apr 17, 2018Chrome 66: Distrust pre-June 2016 certs
Oct 16, 2018Chrome 70: Full distrust of old infrastructure

Total timeline from first incident to full distrust: ~3 years

The Migration

Replacing one-third of the internet's certificates was a massive undertaking.

Who Had to Act

Every website using a certificate from:

SymantecVeriSignThawteGeoTrustRapidSSLEquifax

The Options

Option 1

Get new certificate from DigiCert (using Symantec brand) - issued from trusted infrastructure

Option 2

Switch to another CA entirely - Let's Encrypt, Sectigo, GlobalSign, etc.

The Chaos

Despite over a year of warning:

  • Many sites missed the deadline
  • Some enterprise systems couldn't be updated quickly
  • Legacy hardware (point-of-sale terminals, IoT devices) had problems
  • Third-party tools and services broke when their certs weren't replaced

The Lessons

1.Size Doesn't Equal Trust

Symantec was the biggest CA on the internet. They had VeriSign's legacy, Norton's brand recognition, and millions of customers.

None of that protected them when they couldn't follow the rules. Market share doesn't equal competence.

2.Technical Controls Beat Trust

Symantec trusted their RA partners to do the right thing. They didn't have technical controls preventing abuse.

In security, "trust but verify" isn't enough. You need technical enforcement.

3.Acquisition Without Integration Is Dangerous

Symantec grew by buying VeriSign, Thawte, and GeoTrust. But they never properly unified the security practices.

When acquiring CA operations, you inherit their problems. Integration isn't optional.

4.Gradual Distrust Is Possible

Unlike DigiNotar's instant death, Symantec got 18+ months to wind down. This gave customers time to migrate.

For large CAs, browsers may choose gradual distrust - but this isn't guaranteed.

5.The Industry Consolidates

After Symantec's fall: DigiCert became the dominant commercial CA, Let's Encrypt became the dominant free CA, the "middle tier" mostly disappeared.

CA failures accelerate market consolidation.

Symantec vs. Other CA Failures

Symantec (2017)DigiNotar (2011)WoSign (2016)Entrust (2024)
Root causePartner oversightExternal breachDeliberate deceptionCompliance refusal
Scale~30% of internetDutch governmentFree cert usersEnterprise customers
Warning period18 months3 days14 months5 months
OutcomeSold to DigiCertBankruptShut downStill operating
Human impactBusiness disruptionPossible deathsBusiness disruptionBusiness disruption

What Makes Symantec Different

  • Unlike DigiNotar: Not a security breach - internal compliance failures
  • Unlike WoSign: Not deliberate deception - just negligence at scale
  • Unlike Entrust: Not arguing with the rules - just not following them

Symantec's failure was about scale without oversight. They grew too big and didn't maintain the controls their size demanded.

FAQ

Were Symantec certificates ever used for attacks?

No evidence of malicious use. The certificates were improperly validated, but weren't used for man-in-the-middle attacks or fraud (unlike DigiNotar).

Why did Google give Symantec so much time?

Breaking one-third of the internet overnight would have caused massive collateral damage. The gradual approach balanced security with stability.

Are Symantec-branded certificates safe to use now?

Yes. Since December 2017, "Symantec" certificates are actually issued by DigiCert infrastructure. The brand names continue, but the problematic infrastructure is gone.

What happened to Symantec's other security products?

Symantec (now NortonLifeLock/Gen Digital) continues to sell antivirus and security software. Only the CA business was affected.

Could this happen to DigiCert now?

Any CA could face distrust if they fail to maintain compliance. DigiCert has a strong reputation, but the rules apply to everyone equally.

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