# Safari Autofill Glitch Causes Credit Card Expiration Date Errors Users report Safari consistently miscalculates credit card expiration months during form autofill processes. - **Source:** [www.theregister.com - Articles](https://brifing.si/source/2c34ea50-d341-4a10-925d-12c012a9ad10) - **Published:** 2026-11-06 - **Topic:** [technology](https://brifing.si/c/technology) - **Original article:** - **On Brifing:** https://brifing.si/s/2f1d732f-ddcd-4c7d-8a10-2712c358b525 ## Persistent Autofill Date Errors Apple Safari users have reported a recurring bug where the browser autofill feature incorrectly modifies credit card expiration dates. The issue involves the month field shifting backward by one, causing payment failures on websites. This behavior has been documented in various user forums and Reddit threads since at least 2017. ## Historical User Reports Complaints regarding this specific glitch span several years, with users noting the error persists even after upgrading to new hardware. One user reported that moving between time zones triggered the change, while others noted the shift occurs randomly. Despite these consistent reports, the issue remains unresolved for many affected customers. ## Technical Root Cause Speculation Experts suggest the error may stem from how Safari handles date components within its code. If the browser stores expiration dates using Swift's DateComponent type with UTC as the time zone identifier, local time zone offsets could cause the date to shift backward, effectively changing the month during the form submission process. ## WebKit Versus Safari Code Recent investigations into the bug suggest the flaw resides within Apple-owned Safari code rather than the open-source WebKit engine. This distinction is crucial as it points toward proprietary browser features as the source of the error. Apple has not provided a public acknowledgment or a definitive fix for this specific behavior. ## Inconsistency in Data Handling A notable aspect of this bug is that the credit card information remains stored correctly within the browser's settings menu. The off-by-one error occurs exclusively during the form-filling process. This indicates that the data corruption happens during the retrieval or injection phase, rather than within the underlying stored user data. ## Limited Support Guidance Apple support has reportedly advised affected users to clear their browser cache and re-enter credit card details to resolve the issue. While this may provide a temporary workaround for some, it does not address the underlying logic error. The lack of a permanent fix continues to frustrate long-term browser users. ## Lack of Public Transparency Apple does not maintain a public bug database, making it difficult for users to track the status of known issues. Furthermore, community-maintained resources like OpenRadar provide no additional insight into this specific autofill problem. This opacity leaves users relying on anecdotal evidence and forum discussions to understand the technical glitch. ## Implications for Digital Payments The reliability of browser autofill is essential for seamless e-commerce transactions. When a browser alters sensitive financial data like expiration dates, it creates friction and potential payment declines for consumers. This ongoing issue highlights the challenges of managing time-sensitive data across different time zones within complex browser software architectures. ## Sources covering this story - https://www.theregister.com/applications/2026/11/06/safaris-autofill-feature-may-be-distorting-time/5308006 — --- _Summary written by Brifing from the original reporting. Copyright in the original article belongs to its publisher; read the full piece at the link above._