Curriculum·S202 Token Analysis and Tokenomics·about 40 min
Supply mechanics
By the end of this lesson you can
- →Distinguish circulating, total and maximum supply, and say which of the three is a fact
- →Determine whether a supply cap is enforced by code or by a party who could change it
- →Compute a per-token figure correctly, and identify the supply number a quoted market cap actually used
- →Inspect a token contract for the four permissions that make any published supply provisional
Sophomore · enrolled learners
This lesson opens with Ankr aBNBc, December 2022.
- What happened
- On 2 December 2022 an attacker obtained the private key of Ankr's deployer account, reportedly through a combination of social engineering and a malicious code package attributed to a former team member. Because the aBNBc token contract was upgradeable, the attacker replaced its implementation with a malicious one and minted 10,000,000,000,000 aBNBc to their own address, then sold into the available liquidity. The price fell about 99.5 percent, from $303.89 to $1.53, within hours. Roughly $5M was drained from the pool, and the project asked exchanges to halt trading.
- The decision point
- Nothing about the published supply was wrong on the day before. What was wrong was the belief that a published supply describes a constraint. The contract was upgradeable and held a mint capability behind a single key, which means the supply figure was a statement of current intent by whoever controlled that key, and it was accurate right up until it was not.
- Recorded loss
- $5,000,000
What you will be able to answer
- →Which supply figure is a fact?
- →What makes a supply cap real?
- →What four permissions make a supply provisional?
- →Which supply does a quoted market cap use?
Orientation and Year One are open: anyone can read them without an account. From Year Two onward the lessons are for enrolled learners, because progress through the later years only means anything if it is tracked against a record.
It is free. We do not sell the list and there is nothing to buy at the end of it.
Sources and review
- https://www.ankr.com/blog/after-action-report-our-findings-from-abnbc-token-exploit/
- https://cointelegraph.com/news/ankr-confirms-exploit-asks-for-immediate-trading-halt
- https://medium.com/neptune-mutual/taking-a-closer-look-at-ankr-hack-7c6f57ee8d25
- https://public.bnbstatic.com/static/files/research/low-float-and-high-fdv-how-did-we-get-here.pdf
Confidence high·Volatility medium·Reviewed 2026-08-05·Owner unassigned
Contested
Ankr's own post-incident report attributes the key compromise to a former team member conducting a social engineering and supply chain attack. That account is the company's and the specifics have not been independently adjudicated. Describe the mechanism, which is not disputed, rather than the attribution.
Circulating supply methodology differs between data providers and is not standardized, so two reputable sites can publish different market caps for the same asset. Never present a market cap as a measured quantity; it is a product of a price from one venue and an estimate from one provider.