On 21 October, browsers worldwide finished distrusting certificates from Bengaluru-based eMudhra after its private keys turned out to be guessable in a fraction of a second, and the PHP project shipped emergency fixes for two critical flaws in the language behind most of the world’s websites. CERT-In issued advisories on both. Neither involves a confirmed mass breach yet, but both show how much depends on infrastructure most users never see.
Every secure website visit rests on two things that ordinary users never think about: digital certificates, which prove that a website is who it claims to be, and the server software that builds the page. On Wednesday 21 October, both came under strain, and India has direct stakes in each.
The eMudhra keys: a number below 256
eMudhra Limited is a licensed certifying authority based in Bengaluru, and one of the few Indian companies whose root certificates are trusted by the major browsers. According to ThePrint, an independent researcher identified only as “Wayne” found on the evening of 17 October that eight of its intermediate certificates had critically weak private keys. At 11:35 pm IST he emailed Apple, Google, Microsoft, Mozilla and eMudhra, proving his point by signing a message with each key.
The weakness was stark. Elliptic-curve private keys should be numbers roughly 115 digits long, chosen at random. Mozilla engineer Dennis Jackson said all eight were numbers below 256; one was the number 4. Trying every possibility takes a fraction of a second, and Jackson said AI tools recovered the keys on the first attempt from a basic prompt. Mozilla said the impact “could not be higher”.
The browser makers moved quickly:
- Google blocked the six website (TLS) intermediates in Chrome within 1 hour and 40 minutes of the report, and found no similar flaw at other certificate authorities.
- Mozilla blocked them the same night and, on 20 October, removed the emSign ECC Root CA – G3 root.
- Apple and Microsoft blocked the certificates on 19 and 20 October respectively.
- Sectigo, a US authority that had cross-signed the same certificates, revoked its versions.
Google will remove the emSign ECC Root CA – G3 from Chrome on 27 October, and is examining whether eMudhra’s remaining root should stay trusted. The other two intermediates were for code signing, which verifies that software comes from a genuine publisher.
How it happened
eMudhra’s explanation, as reported by ThePrint, is that the keys were generated on 30 April 2025 inside hardware security modules, then wrapped and unwrapped for transfer to data centres in the US and Europe. A flaw in the transfer script created a second, weak set of keys with similar names, and staff used the wrong set. The company says human errors occurred at several steps, only one of the eight keys was ever put into use, and none issued certificates to end customers. Google found no website certificates from these intermediates in public Certificate Transparency logs.
In a stock-exchange filing, eMudhra said its systems were not breached, no data was lost, its Indian digital signature certificate and eSign services run on separate systems, and the affected business is about 1% of revenue. About 30,000 customer certificates under the removed root must migrate to its other root. These are the company’s statements and have not been independently verified. Its shares fell 20% to their lower circuit of ₹432 on 21 October.
CERT-In’s advisory on Wednesday said the keys were generated without sufficient randomness and listed the risks: forged website certificates, interception of encrypted traffic, stolen credentials and malware signed to look legitimate. It asked organisations to update browsers and operating systems, refresh trusted-certificate lists, replace certificates in the affected chain and never bypass certificate warnings.
PHP2Shell: a decade of exposure
On the same day, the PHP project released versions 8.5.12, 8.4.27, 8.3.36 and 8.2.35 to fix two vulnerabilities, CVE-2026-109618 and CVE-2026-109619, collectively called “PHP2Shell”. Both allow an unauthenticated attacker to run code on a web server; Wiz rates their severity at up to CVSS 9.2.
According to BleepingComputer, both stem from PHP leaving memory in a corrupted state when a request ends abnormally. They affect every PHP setup that serves web requests, including PHP-FPM, Apache with mod_php and LiteSpeed. The PHP team called mod_php the highest risk, because a demonstrated exploit fires “before any application code runs”. Wiz says every PHP release of the past decade, back to 5.4, is affected by at least one of the flaws.
The flaws were found by researchers at Wiz, Calif and OpenAI. Wiz says it used frontier AI models, including Google’s Gemini 4 Argon and OpenAI’s GPT-5.6 Sol, and that “Gemini 4 Argon made an invaluable contribution to finding the vulnerability”. These are the companies’ own accounts. Wiz’s timeline shows the first flaw was found on 19 August and reported to PHP on 24 August, two months before the fix.
According to The Hacker News, the release was brought forward after details leaked on 20 October. Cloudflare’s chief technology officer, Dane Knecht, said the company was already seeing early attacks and had deployed temporary firewall rules. The UK’s National Cyber Security Centre told organisations to patch immediately or take systems offline.
Why India should pay attention
PHP runs much of the Indian web: WordPress sites, university and government portals, small e-commerce shops and legacy enterprise systems. Inc42 reported early on 22 October that CERT-In has warned of a “high risk of remote code execution and complete system compromise”, recommending restricted access, web application firewalls, log monitoring and backup checks. Many Indian organisations depend on shared hosting providers or outside developers and may not control their PHP version at all. Sites on PHP 8.1 or older receive no official updates and must upgrade.
The eMudhra case raises a different question: whether an Indian certifying authority can retain global browser trust. The Controller of Certifying Authorities licenses Indian CAs under the IT Act, but browser trust is granted separately by the browser makers’ own programmes, and it is those programmes that will decide eMudhra’s future.
The common lesson
Neither episode is yet a confirmed mass compromise. Both, however, reflect the same shift: AI tools are compressing the time between a weakness existing and someone exploiting it. A key that once needed a specialist to spot can now be recovered by a chatbot, and decade-old memory bugs are being found by models. For defenders, the window for patching is shrinking accordingly.
