SlowMist Warns Bitcoin (BTC) Platforms of PHP Flaws Scoring 9.2 Out of 10
Key Takeaways
- •SlowMist has cautioned Bitcoin platform operators about PHP vulnerabilities rated 9.2 out of 10, a severity classified as Critical under the CVSS system.
- •PHP's widespread deployment across websites and backend services means critical flaws in the language can affect a broad range of platforms, including those run by cryptocurrency businesses.
- •A COINOTAG analysis found that 6.04 million BTC, representing 30.2% of the issued supply, is held in outputs whose public keys are already visible on the blockchain.
- •Exposed public keys could theoretically allow a sufficiently capable quantum computer running Shor's algorithm to derive the corresponding private keys.
- •Bitcoin's supply is capped at 21 million coins, and the cited figures indicate roughly 20 million have been issued to date.
SlowMist Warns Bitcoin (BTC) Platforms of PHP Flaws Scoring 9.2 Out of 10
October 21, 2026 — SlowMist, the blockchain security firm, has warned operators of Bitcoin (BTC) platforms about vulnerabilities in PHP carrying a severity score of 9.2 out of 10 — a level that falls within the "Critical" band of the Common Vulnerability Scoring System (CVSS), which grades software flaws on a 10-point scale and reserves its top category for scores of 9.0 and above.
PHP is among the most widely deployed server-side scripting languages on the web, powering a substantial share of websites and backend services. Critical flaws in the language are therefore closely monitored by security teams, since affected components can appear across a broad range of online platforms, including services operated by cryptocurrency businesses. Disclosures at this severity level typically prompt operators of web-facing services to check which PHP versions they run in production and to watch for upstream fix releases.
SlowMist, which specializes in blockchain threat intelligence, security audits and anti-money-laundering analysis, regularly issues advisories to exchanges, wallet providers and other digital-asset service operators.
COINOTAG Update — 23:56 UTC: An analysis of public-key visibility finds that 6.04 million BTC, equal to 30.2% of issued supply, sits in outputs whose public keys are already exposed on-chain, leaving them theoretically open to a future quantum attacker running Shor's algorithm.
The exposure stems from how Bitcoin's address system works: a standard address is a hash of a public key, so the underlying key generally stays hidden until funds are moved, at which point it appears in the transaction data. Certain output types record the public key directly, leaving it permanently readable on the blockchain.
Shor's algorithm is a quantum-computing method capable of solving the discrete logarithm problem that underpins Bitcoin's elliptic-curve signatures; given a public key, a sufficiently capable quantum computer could in principle derive the corresponding private key. Bitcoin's total supply is capped at 21 million coins, and the figures cited in the analysis imply that around 20 million BTC have been issued to date.
This content was first published on COINOTAG: https://en.coinotag.com/slowmist-warns-bitcoin-btc-platforms-php-flaws-9-2
