Tech & World News: 5 November 2026 | AI Stock Slump, Bank of England Hike, GPT-6 Cyber & DigiCert Breach

5 November 2026 edition · Published 5 November 2026 · Research cutoff: 19:00 GMT, 5 November 2026. AI stocks fell sharply again on Wall Street, the Bank of England raised interest rates for the first time in more than three years, OpenAI launched a cybersecurity model, and DigiCert confirmed a data breach. One of these stories was still developing at our cutoff, and it is labelled below.

Summary

AI stocks (developing): by 12:26pm in New York, the S&P 500 was down 3.5% and the Nasdaq 4.7%. Nvidia fell 7.5% and AMD 14.6%, according to the Associated Press. These are midday figures; US markets were still open at our cutoff.
Bank of England: Bank Rate raised by 0.25 percentage points to 4%, by an 8–1 vote. Inflation is expected to reach around 5% by the middle of 2027.
OpenAI GPT-6 Cyber: a security-focused model that OpenAI says found 81 previously unknown, high-severity Firefox vulnerabilities. Access is limited to approved security customers.
DigiCert: the certificate authority confirmed a breach after a 2025 server migration exposed an internal system. Some customers’ identity documents were involved.

1. AI stocks get hammered again (developing)

Stocks tied to the AI data-centre build-out fell heavily on Thursday 5 November. The Associated Press reported that, as of 12:26pm Eastern time (17:26 GMT), the S&P 500 was down 3.5% and on track for its worst day since the April 2025 tariff shock. The Dow Jones Industrial Average was down 1,433 points, or 2.7%, and the Nasdaq Composite was 4.7% lower.

Nvidia fell 7.5%, a day after dropping 3.2%. AMD fell 14.6%, and CoreWeave, which rents AI chips over the cloud, fell 12.1%. Reuters reported that the Philadelphia semiconductor index fell as much as 11% during the session, and that the Nasdaq’s slide of as much as 5% would confirm a correction (a 10% fall from its recent high).

Why it matters: AI chipmakers are now among the largest companies on Wall Street, so their moves drive the whole index. AP and Reuters both point to two worries: high borrowing costs make expensive data centres harder to finance, and Tuesday’s US election results, including Democratic gains and local ballot measures, raised the prospect of limits or pauses on new data-centre construction.

Note: these are intraday figures. Closing prices were not available at our research cutoff and may differ.

AI stock selloff, midday 5 November 2026: S&P 500 down 3.5%, Nvidia down 7.5%, AMD down 14.6% (AP) — Midday figures, 12:26pm ET, 5 November 2026. Source: Associated Press.

2. The Bank of England raises rates to 4%

The Bank of England’s Monetary Policy Committee voted by 8–1 to raise Bank Rate by 0.25 percentage points, from 3.75% to 4%. One member voted for a larger rise to 4.25%. It is the Bank’s first rate increase since August 2023 (CNBC).

In its Monetary Policy Summary, the Bank says the conflict in the Middle East is now in its ninth month and global energy prices have kept rising. UK CPI inflation rose to 3.5% in September, and the Bank expects it to reach around 5% by the middle of 2027 before falling back. It noted “limited evidence” so far of knock-on effects on other prices and wages, but judged that enough inflationary pressure is building to justify a rise. The next decision is due on 17 December 2026.

Why it matters: for UK households, a higher Bank Rate typically feeds through to tracker and variable mortgages and to savings rates. The Bank also says policy is “not on a pre-set path”, so future moves depend on how energy prices and inflation develop.

Bank of England raises Bank Rate from 3.75% to 4%, MPC vote 8-1, inflation forecast near 5% by mid-2027 — Source: Bank of England Monetary Policy Summary, 5 November 2026.

3. OpenAI launches GPT-6 Cyber

OpenAI announced GPT-6 Cyber on 5 November, a model trained to find and validate exploitable software vulnerabilities while staying within the scope researchers set. OpenAI says researchers used it to identify 81 previously unknown, high-severity vulnerabilities in Firefox and to develop 948 privilege-escalation exploits for Linux, and that Mozilla has released fixes for many of the Firefox issues.

Access is restricted. Fortune and The Next Web report that the model is initially available only to a small group of approved customers in OpenAI’s Daybreak Red programme, through the API and Codex. The Next Web reports that OpenAI rated the model “Critical” for cybersecurity under its Preparedness Framework.

Why it matters: AI models are getting better at finding and exploiting bugs in heavily tested software. That helps defenders patch faster, but the same skills could help attackers, which is why access is gated. The bug counts are OpenAI’s own figures.

4. DigiCert confirms a data breach

DigiCert, one of the largest certificate authorities, has confirmed a data breach and begun notifying affected customers, BleepingComputer reported on 5 November. According to an incident report cited by BleepingComputer, a server migration in February 2025 mistakenly exposed an internal business system to the internet that was previously reachable only via VPN. A self-registration feature and an authorisation flaw allowed outsiders to view archived customer information in read-only mode.

The exposed data included names, business email addresses, phone numbers and business addresses, and for some customers identity documents such as driving licences, passports or utility bills. DigiCert says it is still reviewing documents to identify everyone affected.

Why it matters: identity documents are valuable for fraud and impersonation. DigiCert customers should watch for its notification and be alert to targeted phishing that uses their details.

What to watch next

Where US markets close on 5 November, and whether the Nasdaq formally confirms a correction.
The Bank of England’s next decision on 17 December 2026, and energy prices tied to the Middle East conflict.
Wider availability of GPT-6 Cyber to Daybreak Red customers, and Mozilla’s Firefox security advisories.
DigiCert’s completed review of affected identity documents.

Editorial note: this roundup was researched and published on 5 November 2026 with a research cutoff of 19:00 GMT. The video uses original animated graphics, AI English narration and quiet original music. Nothing here is financial advice.