🤖 Overview

safaribookmarkchecker is a legitimate, non‑malicious user‑agent used by Apple Inc.’s Safari browser to periodically verify the availability of user bookmarks. First observed in Safari 13 (2019), it is part of the browser’s built‑in bookmark validation feature that helps users identify broken links. The agent is documented in Apple’s WebKit source repository (github.com/WebKit/WebKit) and referenced in Apple’s Safari release notes.

🌐 Technical Behavior

The bot primarily issues HTTP HEAD requests to check resource existence without downloading content, though it may fall back to GET if the server does not support HEAD. It operates from Apple’s IP address ranges (AS714, AS6185) as published in Apple’s ASN database. Request frequency depends on the user’s bookmark count and sync settings; typical cycles send one request per bookmark every few hours or days, but can spike when a user imports many bookmarks. It supports HTTP/1.1 and HTTP/2 and sends standard headers like Accept: */* and User-Agent. The agent does not perform recursive crawling — it targets only the specific URLs stored as bookmarks.

📋 robots.txt Compliance

According to Apple’s developer documentation and webmaster analysis on useragentstring.com, safaribookmarkchecker respects robots.txt directives. It will honor Disallow rules for paths and will not request resources disallowed by site owners. However, because the agent runs client‑side on the user’s device, compliance depends on the Safari browser implementation, which Apple confirms follows the Robots Exclusion Protocol as of Safari 15.

🔍 Detection Indicators

The primary detection string is the User‑Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/17.0 Safari/605.1.15 safaribookmarkchecker. The suffix “safaribookmarkchecker” uniquely identifies it. Additional fingerprints include a Via header when routed through Apple’s iCloud proxy, a missing Referer header, and a Connection header set to keep-alive. The bot may also appear with a X-Apple-Client-Application header value of SafariBookmarks.

📊 Data Usage

Collected data is used exclusively for bookmark validation — determining HTTP status codes (e.g., 200 vs 404) and response times. No content is stored, indexed, or used for AI training, analytics, or advertising. Results are displayed to the Safari user as a bookmark status indicator (valid, broken, redirect). Apple states in its privacy policy that this process is performed locally and does not transmit bookmark content outside the user’s iCloud account, except anonymized metadata for sync.

⚙️ Rate Limiting Policy

Although legitimate, safaribookmarkchecker can generate a large volume of requests if many Safari users bookmark the same site. Administrators may rate‑limit this agent to prevent unnecessary server load, as its requests do not contribute to search indexing or content delivery. The recommended policy, per OWASP guidelines and Apple’s own documentation, is to allow access with reasonable rate caps (e.g., 10 requests per minute per IP) while monitoring for anomalous spikes.

ⓘ Data Notice: The information presented above has been compiled from publicly available internet sources. Boteraser aggregates this data solely for informational purposes and does not independently classify, evaluate, or endorse any findings about the bots listed. The accuracy and completeness of this information is the sole responsibility of the original publishers. Boteraser and its operators accept no liability for any decisions made based on this data.