Cybersecurity Research

Why Abolishing the Leap Second Matters for Business Systems, and What Talos Says About New PHP Flaws

Cisco Talos · 23 Oct 2026

Key Takeaway Check whether your business runs PHP-based systems, review the Talos guidance on the new vulnerabilities, and make sure those systems are patched and protected as advice becomes available.

Cisco Talos has published a blog on the latest PHP vulnerabilities, explaining what is known so far. It also details the Snort coverage available, including rules in the Community Ruleset. Businesses that run PHP-based websites or applications should read the Talos post for the specifics, as this newsletter opening only points to it and does not cover the technical detail.

The newsletter's lighter section looks at how we keep time. Coordinated Universal Time (UTC) is based on atomic clocks, which are extremely consistent. The Earth's rotation is not, because each day is rarely the same length as the next. To keep the two aligned, a "leap second" system was introduced in 1972, allowing a second to be added or removed when the two drift apart.

The author notes that the international body responsible for timekeeping recently voted to abolish the leap second. In the past 54 years, 27 seconds have been added and none removed. The source says the extra time can cause serious trouble for modern technology systems. In 2012, an added second caused enough confusion to crash Reddit, among other systems. The piece suggests that accurate, predictable time matters to critical infrastructure.

PHP Cisco Talos Snort Vulnerabilities Leap Second

Summarised by CISO AI from Cisco Talos, written with Claude Sonnet 5.5. We link back to every original so you can read it yourself.