Key facts
- A critical XRP Ledger bug, undetected for over a decade, has been patched.
- The flaw could have allowed attackers to silently mint billions of XRP.
- Researchers Cayden Liao and Veria AI discovered the bug on September 22, 2026.
- An emergency fix was deployed in xrpld 3.4.1 on September 25, 2026.
- RippleX confirmed no evidence of exploitation on public networks.
- XRP has a fixed supply of 100 billion tokens, minted in 2012.
A critical bug in the XRP Ledger, which had remained undetected for over a decade, has been patched by RippleX. The flaw, discovered by researchers Cayden Liao and Veria AI on September 22, 2026, could have allowed attackers to silently mint billions of XRP, potentially undermining the token's fixed supply of 100 billion. The vulnerability stemmed from an integer overflow in the payment engine, written around 2015, which incorrectly summed XRP amounts across offers on the built-in decentralized exchange (DEX).
An attacker could have exploited this by placing numerous small, mispriced offers for XRP. Consuming these offers simultaneously would cause a 64-bit counter to overflow and wrap around, allowing the buyer to receive XRP while being charged minimally. The ledger's own "no XRP created" invariant, using the same flawed arithmetic, failed to detect the overflow. The potential cost of such an attack was estimated to be only a few hundred XRP in reserves, most of which was recoverable.
RippleX reproduced the exploit on a standalone server and confirmed that the bug could produce spendable tokens. An emergency fix was released in xrpld version 3.4.1 on September 25, 2026, with over 80% of default UNL validators running the patched version by release day. The public disclosure followed on October 9, 2026, when RippleX stated there was no evidence the flaw was ever exploited on any public network, as normal transaction activity did not reach the arithmetic limits. Realistic offer pricing and supply constraints kept payments clear of the trigger conditions.
The rapid discovery, swift patching, and transparent disclosure are seen as positive signals for institutional adoption, especially as the XRP Ledger sees advancements like the Batch amendment for atomic multi-transaction settlement. With Evernorth's treasury deal and Ripple Prime's expansion into stock trading, the integrity of XRP's fixed supply is a crucial trust anchor for large capital. Meritz Securities is also exploring custody and tokenization with Ripple for Korean capital markets, underscoring the importance of supply integrity.