Bootstrap is an open source frontend toolkit that provides HTML, CSS, and JavaScript components for building responsive websites and web applications. The framework includes a grid system, prebuilt UI components, Sass variables for customization, and JavaScript plugins for interactive elements. UpGuard continuously monitors the security posture of Bootstrap using open-source, commercial, and proprietary threat intelligence feeds. Our analysis is centered on objective, externally verifiable information.
Bootstrap's security rating is based on the analysis of their external attack surface. The higher the rating, the better their security posture. Start a free trial to get a more in-depth risk assessment for Bootstrap.
Last updated April 13, 2026
This vendor risk report is based on UpGuard's continuous monitoring of Bootstrap's security posture using open-source, commercial, and proprietary threat intelligence feeds. The results are summarized into a security rating based on the analysis of hundreds of individual checks across five risk categories: website security, email security, phishing & malware, brand & reputation risk, and network security.
Browsers may display this website's content in frames. This can lead to clickjacking attacks.
No valid Content Security Policy is implemented. This increases the risk of XSS and clickjacking attacks.
Ensuring the server information header is not exposed reduces the ability of attackers to exploit certain vulnerabilities.
Information about specific technology used on the server is obscured.
The website's Referrer Policy is not configured to allow unsafe information to be sent in the referrer header.
Ensuring the ASP.NET version header is not exposing a specific version makes it harder for attackers to exploit certain vulnerabilities.
Ensuring the ASP.NET version header is not exposed makes it harder for attackers to exploit certain vulnerabilities.
Browsers are prevented from interpreting files as a different MIME type to what is specified in the Content-Type HTTP header. This helps mitigate MIME confusion attacks.
The page appears to be maintained.
DMARC policy was not found. This makes it easier for attackers to send email from this domain. A DMARC policy should be deployed for this domain.
Sender Policy Framework (SPF) records prevent spammers from sending messages with forged addresses.
Sender Policy Framework (SPF) record strictly enforces specific domains allowed to send email on its behalf.
Sender Policy Framework (SPF) record passes basic syntax checks.
Sender Policy Framework (SPF) record does not include the ptr mechanism.
The 'HTTP' service is running and exposed to the internet. The configuration of the server should be reviewed and unnecessary ports closed.
The domain does not contain a valid Certification Authority Authorization (CAA) record. A CAA record indicates which Certificate Authorities (CAs) are authorized to issue certificates for a domain.
No unregistered MX records that could lead to receiving mail on behalf of the target organization were detected.
Domain has not expired.
No dangling DNS records that could lead to subdomain takeover were detected.
Domain does not expire within 30 days.
DNSSEC records prevent third parties from forging the records that guarantee a domain's identity.
Domain is not flagged as inactive.
Domain is not pending deletion with the registrar.
Domain is not pending restoration with the registrar.
Domain is protected from unsolicited deletion requests with the registrar or registry.
Domain is protected from unsolicited transfer requests.
Domain is protected from unsolicited update requests with the registrar or registry.
Domain is not under a DNS resolution hold with the registrar.
Domain is not under a DNS resolution hold with the registry itself.
Domain is not prohibited from renewal at the registry itself.
HTTPS is redirected to an insecure protocol. HTTPS requests should not be redirected to insecure protocols, as they do not ensure encrypted communication between the website and its visitors.
Any version of the SSL protocol, and TLS prior to version 1.2, are now considered insecure. The server should disable support for these old protocols.
Weak cipher suites can potentially be broken by a well resourced attacker, and should not be supported by the server unless very old devices or browsers must be supported.
The site's certificate chain was checked against our list of revoked certificates.
SSL is supported for this site.
All HTTP requests are redirected to HTTPS.
The site's hostname matches the SSL certificate.
SSL certificate has not expired.
The certificate presented by this domain was issued by a trusted certificate authority.
With HSTS enforced, people browsing this site are less susceptible to man-in-the-middle attacks.
A complete SSL certificate chain was presented by the server for this domain.
SSL intermediate and root certificates do not expire within 20 days.
The SSL certificate presented by the server has an expiration period shorter than 398 days.
SSL certificate does not expire in less than 20% of its total valid period.
Industry standard SHA-256 encryption in use.
Being included on the preload list gives the highest level of protection against MITM attacks for users of all major browsers.
The site's public certificate provides at least 112 bits of security strength.
Infostealer malware has been detected on systems associated with this organization, indicating a potential data breach.
No cloud storage service configured to allow anonymous file listing was detected.
The domain index is not a listable directory.
This website does not appear to contain malicious code.
This IP/domain has not been reported as a source of botnet activity in the last 30 days.
This IP/domain did not appear on any list of IPs and domains known to perform brute force login attempts in the last 30 days.
This IP/domain has been reported for distributing malware in the last 30 days.
This IP/domain has not been reported for performing unsolicited scanning in the last 30 days.
This website does not appear to be attempting to install unwanted software.
This site does not appear to be a forgery or imitation of another website.
This IP/domain has not been reported as a phishing site in the last 30 days.
This IP/domain has not been reported as a source of botnet activity in the last 90 days.
This IP/domain did not appear on any list of IPs and domains known to perform brute force login attempts in the last 90 days.
This IP/domain has been reported for distributing malware in the last 90 days.
This IP/domain has not been reported for performing unsolicited scanning in the last 90 days.
This IP/domain has not been reported as a phishing site in the last 90 days.
A bug in OpenSSL's implementation of the TLS heartbeat extension allows access to portions of memory on the targeted host e.g. cryptographic keys and passwords.
The server does not support SSLv3, and is not vulnerable to the POODLE attack.
The server does not offer RSA_EXPORT cipher suites, so clients are not vulnerable to the FREAK attack.
The server is using strong Diffie-Hellman parameters and is not vulnerable to the Logjam attack.
Compare Bootstrap's security performance with other companies in their industry.
Airbnb operates an online marketplace that connects travelers with hosts who offer short-term lodging accommodations and tourism experiences. The platform facilitates bookings for vacation rentals, private rooms, and unique stays in properties worldwide.
Microsoft develops and licenses software products, devices, and services. The company's core offerings include the Windows operating system, Office productivity suite, Azure cloud computing platform, and Xbox gaming consoles.
Yahoo! operates an internet media platform providing web portal services including email, news aggregation, search functionality, weather information, and financial data. The company delivers content across multiple categories such as sports, entertainment, lifestyle, and politics to users in various international markets.
HP manufactures and sells personal computing devices and printing equipment, including laptops, desktop computers, printers, ink cartridges, and related accessories. The company offers product lines for consumer, gaming, and business markets.
Netflix operates a subscription-based streaming service that provides on-demand access to movies, television shows, documentaries, and original content. The platform allows subscribers to watch unlimited content across internet-connected devices including smart TVs, computers, tablets, and smartphones.
Verizon provides wireless telecommunications services, home internet connectivity, and digital television offerings to consumer and business customers. The company operates mobile networks and fiber-optic infrastructure to deliver voice, data, and video services across the United States.
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