How to Avoid Certificate Outages

A certificate outage happens when an SSL/TLS certificate becomes invalid, expired, or revoked, and avoiding one requires a complete certificate inventory, continuous expiration monitoring, and automated renewal rather than manual tracking.

Avoiding certificate outages requires four things: a centralized inventory of every certificate in use, continuous monitoring for approaching expirations, automated renewal so nothing depends on someone remembering a date, and redundant configurations for critical services. Expired certificates remain one of the most common, and most preventable, causes of unplanned downtime.

Key Takeaways

• Expired certificates are a leading cause of preventable outages. Well-known incidents at Microsoft Teams and Ericsson’s core telecom network were both traced to expired certificates, not sophisticated attacks.
• Manual tracking fails at scale, not from lack of effort. Spreadsheet-based tracking works until certificate counts grow past what one person can reliably check on schedule.
• Monitoring tools beat manual checks and CA email reminders. Automated health checks integrated into existing infrastructure monitoring catch problems that inbox-based reminders miss.
• Shorter certificate validity multiplies outage risk if nothing changes. As validity periods shrink toward 47 days under CA/Browser Forum Ballot SC-081v3, the same manual process fails more often, not less.
• Redundancy limits the blast radius of a single certificate failure. Backup certificates and load-balanced configurations for critical services prevent one lapsed certificate from taking down an entire service.

What Causes Certificate Outages

• Most certificate outages trace back to one of five recurring causes, not a single unpredictable failure.

• Expired certificates. The most common cause: a certificate simply was not renewed before its validity period ended.
• Revoked certificates. A certificate revoked for a security incident causes an outage until a replacement is issued and deployed.
• Human error. Mistakes during installation, configuration, or renewal cause outages even when the certificate itself is valid.
• Lack of monitoring. Without proactive tracking, a certificate can lapse with no warning to anyone responsible for it.
• Complex, multi-domain environments. Organizations running many services and domains face more points of failure and more chances for a certificate to be overlooked.

Real-World Certificate Outages

Certificate outages have affected major platforms, not just small or poorly resourced organizations.

Microsoft Teams experienced a widely reported outage in February 2020, later attributed to an expired certificate, that disrupted meetings for users. In December 2018, an expired certificate in Ericsson’s core network software triggered a nationwide outage affecting O2, Tesco Mobile, and Sky Mobile in the UK along with SoftBank in Japan, leaving roughly 32 million O2 subscribers without service for close to 24 hours. Neither incident involved an attacker; both were certificates nobody was tracking until they expired.

How to Prevent Certificate Outages

Six practices, applied together, close most of the gaps that lead to an outage.

1. Maintain a centralized certificate inventory. Track every certificate’s issuance date, expiry date, and owner in one place, not scattered across teams.
2. Set up automated monitoring and alerts. Notifications should fire well ahead of expiration, tuned to the certificate’s actual validity period.
3. Automate renewals wherever possible. Automated renewal removes the single point of failure that a manual reminder represents.
4. Build in redundancy for critical services. Backup certificates and load-balanced configurations prevent a single certificate failure from taking down an entire service.
5. Audit certificates regularly. Periodic audits catch misconfigurations and vulnerabilities that day-to-day monitoring might miss.
6. Train IT staff on certificate management. Understanding renewal processes and the risks of expiration reduces the human error that causes a meaningful share of outages.

How to Know When a Certificate Is About to Expire

Automated tools are more reliable than any manual tracking method for catching an approaching expiration.

• Certificate management platforms. These offer automated monitoring and alerting with enough lead time for renewal.
• Certificate health checks in monitoring tools. Integrating certificate status into existing network and server monitoring catches issues alongside other infrastructure alerts.
• Certificate management APIs. APIs from CAs or management platforms allow programmatic retrieval of expiration data for custom dashboards or workflows.
• Renewal policies with lead time built in. Organizational policy requiring renewal a set number of days before expiration avoids last-minute scrambles.

Manual tracking, calendar reminders, and relying solely on CA notification emails are all weaker alternatives to the options above; each is prone to being missed exactly when it matters most.

What Are the Common Triggers Behind Certificate Failures?

Certificate outages can happen when something goes wrong with the digital certificates that secure websites and online services. These certificates are like electronic IDs that prove a website is trustworthy. When certificates have outages, it’s often because of several reasons that are as follows:

• Expired Certificates

  Certificate outages can occur when website owners or system administrators forget to renew or replace their SSL/TLS certificates after expiration, leading to potential service disruptions.

• Revoked Certificates

  In some cases, certificates are revoked due to security incidents or suspicion of compromise, causing outages until new certificates are issued and deployed.

• Complex Certificate Ecosystem

  The increasing complexity of certificate management, especially in large organizations with multiple services and domains, can lead to misconfigurations and errors that result in outages.

• Human Error

  Mistakes during certificate installation, configuration, or renewal processes can trigger outages, underscoring the importance of proper training and automation.

• Revoked Certificates

  In some cases, certificates are revoked due to security incidents or suspicion of compromise, causing outages until new certificates are issued and deployed.

• Vendor and Third-Party Issues

  Dependency on third-party services or vendors for certificate provisioning and management introduces additional risk factors for potential outages

• Scaling Challenges

  Rapidly growing websites or services may struggle to scale their certificate management systems appropriately, leading to outages during periods of high demand.

• Lack of Monitoring

  Failure to proactively monitor certificate health and expiration dates can result in unexpected outages when certificates become invalid.

• Regulatory Compliance

  Organizations must comply with industry standards and regulations related to certificates, such as the Payment Card Industry Data Security Standard (PCI DSS) or General Data Protection Regulation (GDPR). Failure to meet these requirements can lead to outages and legal consequences.

• Impact on SEO

  Certificate outages can negatively affect search engine rankings, as search engines prioritize secure and accessible websites.

• Customer Trust

  Certificate outages can erode customer trust and confidence in the security and reliability of a website or service.

What are the Effects of Certificate Outages?

Certificate outages can have significant effects on our online experiences. Think of these certificates as the security guards for websites and online services. When they go offline or have problems, it’s like the guards taking a break, and this can lead to various issues.

• Loss of Secure Connections

  The primary effect of a certificate outage is the loss of secure connections between users and the server. Without a valid SSL/TLS certificate, the data transmitted between them is no longer encrypted, leaving it vulnerable to interception by cybercriminals.

• Browser Warnings

  to access a website experiencing a certificate outage, modern browsers display warning messages alerting them that the connection is not secure. This can deter users from proceeding further and may lead to a significant drop in website traffic.

• Data Breach Risk

  During a certificate outage, sensitive information, such as login credentials, credit card details, and personal data, may be exposed to potential cyberattacks. Cybercriminals may exploit the lack of encryption to intercept and misuse this information.

• Loss of Customer Trust

  Certificate outages erode user confidence in a website’s security and reliability. Users who encounter warning messages may perceive the site as untrustworthy, leading to a loss of customer trust and loyalty.

• Negative Reputation Impact

  A prolonged or severe certificate outage can result in negative press and damage the company’s reputation. Public perception of the organization’s security practices may suffer, affecting its brand image.

• Financial Loss

  E-commerce websites or businesses relying heavily on online services may experience financial losses during a certificate outage. Users may abandon shopping carts or avoid conducting transactions due to security concerns.

• Regulatory Non-Compliance

  In cases where SSL/TLS certificates are required to comply with data protection regulations or industry standards, a certificate outage can lead to non-compliance and potential legal consequences.

• Downtime and Service Disruption

  Depending on the severity of the certificate outage and the organization’s response time, the website or online service may experience downtime, rendering it inaccessible to users until the issue is resolved.

• Impact on SEO

  Search engines prioritize secure websites with valid SSL/TLS certificates in their rankings. During a certificate outage, the website’s SEO performance may suffer, leading to reduced online visibility and traffic.

• Customer Trust

  Organizations facing certificate outages may experience increased customer support inquiries from concerned users seeking clarification or assistance, putting additional strain on support resources.

Is Your Organization Prepared for the Certificate Outage Challenge?

Organizations can implement several solutions and best practices to avoid certificate outages and maintain continuous secure operations. There are some key solutions to prevent certificate outages:

• Implementing a centralized certificate management solution to keep track of certificate expiration dates, allowing administrators to take timely action.
• Maintaining a centralized inventory of all SSL/TLS certificates used within the organization, including issuance dates, expiry dates, and renewals.
• Setting up reminders or notifications for certificate renewals to ensure they are not missed or overlooked.
• Implementing redundant certificate configurations with backup certificates for critical services.
• Employing automation tools for handling certificate renewals to reduce manual errors and ensure prompt renewal.
• Conduct regular audits of certificates to identify potential vulnerabilities or misconfigurations and ensure timely renewal.
• Using high availability and load balancing solutions to distribute traffic across servers with valid certificates, preventing single points of failure.
• Monitoring the status and health of certificate authorities used to issue certificates and ensuring they adhere to industry standards.
• Developing a comprehensive incident response plan to facilitate a swift response and recovery in case of a certificate outage.
• Educating employees and IT staff on the importance of certificate management, renewal processes, and the potential risks of certificate expirations.

How to Know When a Certificate is About to Expire?

Knowing when a certificate is about to expire is crucial for preventing certificate outages and ensuring continuous secure connections. Here are several ways to keep track of certificate expiration dates:

• Certificate Management Tools

  Utilize certificate management tools or services that offer automated monitoring and alerting for certificate expiration dates. These tools can send notifications well in advance, allowing sufficient time for certificate renewal. Certificate management tools offer the most efficient and secure way to oversee and maintain digital certificates.

• Certificate Transparency Logs

  Certificate Transparency (CT) logs are publicly accessible repositories that record certificate issuance and expiration information. CT logs can be queried to check the validity period of a certificate and identify when it will expire. It’s advisable not to go for Certificate Transparency logs due to potential privacy concerns and data exposure risks.

• Manual Tracking

  Maintain a centralized certificate inventory with information about all SSL/TLS certificates used within the organization. Set up a schedule to regularly review and track expiration dates manually. Manual tracking is not recommended as it is prone to errors, time-consuming, and lacks the efficiency and security of automated certificate management solutions.

• Certificate Authority Notifications

  Some Certificate Authorities (CAs) send notifications via email or other channels when certificates are about to expire. Keep an eye on these notifications and ensure they don’t get missed. Choosing not to rely solely on Certificate Authority notifications is recommended because they may not provide comprehensive coverage or real-time updates, potentially leaving certificate management vulnerabilities unaddressed.

• Monitor Certificate Health via Monitoring Tools

  Integrate SSL/TLS certificate health checks into your network and server monitoring tools. These checks can provide real-time information about certificate status, including expiration dates. Opting out of monitoring certificate health through monitoring tools is not advisable, as it can lead to inadequate oversight, missed issues, and delayed responses to certificate-related problems, compromising security.

• Use Certificate Management APIs

  If available, use APIs provided by CAs or certificate management platforms to programmatically retrieve certificate details, including expiration dates. Avoiding the use of Certificate Management APIs is not recommended, as they offer essential automation and integration capabilities crucial for efficient certificate management, security, and compliance.

• Set Calendar Reminders

  Manually set reminders in calendars or task management systems to review certificate expirations periodically. This can be a simple yet effective way to stay on top of renewal dates. Neglecting to set calendar reminders is discouraged as it can result in missed certificate-related tasks and renewals, increasing the risk of security breaches and service disruptions.

• Configure Certificate Renewal Policies

  Implement organizational policies that require certificates to be renewed a certain number of days before their expiration dates. This helps avoid last-minute renewals and potential lapses in security. Choosing not to configure certificate renewal policies is not advisable, as it can lead to oversight of expiring certificates and potential security vulnerabilities in your infrastructure.

• Certificate Revocation Check

  Regularly check for certificate revocations, as revoked certificates are no longer valid, and immediate action should be taken to replace them. Deciding against implementing certificate revocation checks is not recommended, as they are essential for promptly identifying compromised or revoked certificates and maintaining the security of your digital environment.

Exploring X.509 Certificate Management Functions

Many companies that deal with online security and digital certificates provide special software called Certificate Management Systems (CMS). These CMS tools help organizations find, recognize, keep track of, notify about, and automatically update and check the installation of new X.509 certificates. To put it simply, when a company or website uses digital certificates to secure their online communication, they need a way to manage and keep these certificates up to date.

The key certificate management functions under the X.509 standard include the following.

• Certificate Issuance

  The process of generating and issuing X.509 certificates to entities after verifying their identity and credentials. This typically involves a certificate authority (CA) or a registration authority (RA) validating the requester’s identity before issuing the certificate.

• Certificate Renewal

  X.509 certificates have a defined validity period, after which they expire. Certificate renewal involves extending the certificate’s validity to continue its usage securely. Renewal typically requires revalidating the identity of the certificate holder.

• Certificate Revocation

  In certain cases, a certificate might need to be revoked before its expiration date due to reasons such as a compromise of the private key or changes in the certificate holder’s status. Certificate revocation lists (CRLs) or online certificate status protocols (OCSP) are used to inform relying parties about revoked certificates.

• Certificate Validation

  Before trusting a certificate, relying parties (e.g., web browsers) validate its authenticity, ensuring it is issued by a trusted CA and not expired or revoked.

• Certificate Storage and Retrieval

  Securely managing the storage and retrieval of X.509 certificates is crucial. Certificate stores and repositories help store and distribute certificates to the appropriate entities.

• Certificate Policy Management

  X.509 certificates may be issued and used according to specific policies defined by organizations or industries. Certificate management involves implementing and enforcing these policies.

How can Encryption Consulting help?

CertSecure Manager centralizes certificate inventory, monitoring, and automated renewal so expiration dates never depend on someone remembering a date. Real-time alerts and reporting flag certificates approaching expiry with enough lead time to act, before they become an outage. Backed by ISO/IEC 27001:2022 and SOC 2 certified practices.

Frequently Asked Questions

What is the most common cause of certificate outages?

Expired certificates that were not renewed in time. This is more often a monitoring and process failure than a technical one: the certificate itself was fine, but nobody tracked its expiration date closely enough to renew it beforehand.

How much lead time should I have before a certificate expires?

This depends on your renewal process, but automated systems typically alert well before expiration, and organizational policy should require renewal with enough buffer to handle unexpected delays. As certificate validity periods shorten toward 47 days under CA/Browser Forum Ballot SC-081v3, that buffer needs to scale down proportionally too.

Can a certificate outage happen even with monitoring in place?

Yes, if monitoring is not tuned correctly or if a certificate exists outside the monitored inventory entirely. This is why certificate discovery, finding every certificate an organization actually runs, is a prerequisite for monitoring to be complete.

Do certificate outages only affect large enterprises?

No. Certificate outages have affected major platforms like Microsoft Teams and large telecom operators, but any organization with unmanaged or unmonitored certificates faces the same risk. Scale changes the blast radius, not the underlying cause.

Prevent Certificate Outages Before They Happen

See CertSecure Manager in action for centralized inventory, monitoring, and automated renewal that keeps certificates from becoming outages.