@VCestarii

Vinteum Fellow | PGP: 0x82BF7385AF227906 https://xitter.cf/t.co/dCLpfweKn3

viniciuscestari.dev
Joined September 2023
  • Tweets174
  • Following228
  • Followers105
10Media
READ: Vinicius Cestarii (@VCestarii) is hunting mutants in bitcoin-core Read his latest on how he found two fixes for bitcoin core using his custom mutant harness 👇
ViniciusCestarii@VCestariiSep 9
I built an agent to hunt for live mutants in Bitcoin Core's consensus-critical code. It found several gaps that led to two Bitcoin Core PRs adding tests for things the existing suite missed. I wrote about how it works and what it found: viniciuscestari.dev/posts/hu…
2
4
545
I built an agent to hunt for live mutants in Bitcoin Core's consensus-critical code. It found several gaps that led to two Bitcoin Core PRs adding tests for things the existing suite missed. I wrote about how it works and what it found: viniciuscestari.dev/posts/hu…
1
6
1
18
1,150
I didn't have the full picture of Bitcoin mining before this week. Going from protocol down to the hardware and seeing every piece fit together was really cool!!
Vinteum
@Vinteum_orgSep 1
Our latest Deep Dive went from the history of pooled mining to Stratum V2, P2Poolv2, Bitcoin Core IPC, firmware, and eventually silicon. Five days of reading specs, reading code, challenging assumptions, and finding better questions. blog.vinteum.org/inside-a-vi…
1
1
11
666
ViniciusCestarii retweeted
Bruno Garcia
@brrrunogAug 28
Preprint of my research paper: "Investigating the application of differential fuzzing to support the identification and suppression of equivalent mutants: An experimental study" researchsquare.com/article/r…

Investigating the application of differential fuzzing to support the identification and suppression...

Mutation testing is widely used to assess the adequacy of test suite; however, its practical adoption is constrained by the persistent problem of equivalent mutants, i.e., mutants whose observable...

researchsquare.com
2
10
1
24
1,669
ViniciusCestarii retweeted
E r i c k λ@iamflopsAug 27
I've written my first public vulnerability disclosure, detailing a DoS vulnerability I found in Core Lightning. An attacker can crash a node simply by opening a connection and flooding it with ping messages. Blog post: erickcestari.dev/blog/ping-f… Delving: delvingbitcoin.org/t/disclos…

Crashing a Lightning node with a flood of pings - Erick Cestari

Core Lightning answered every ping and gossip query even when the peer refused to read the replies. One connection could grow the outgoing queue until the node ran out of memory. Here's the OOM, and...

erickcestari.dev
4
16
40
1,589
I scanned ~16,800 public Bitcoin nodes with nmap to fingerprint what OS they're actually running. 69.2% Linux. 4.6% Windows. 0.8% macOS. One lonely Solaris box. Open data, open source, and a dashboard to explore it 👇 github.com/ViniciusCestarii/…
7
7
5
83
19,888
These are best-effort guesses, not facts. nmap infers OS from TCP, UDP and ICMP stack behaviour and returns a confidence score. Some fingerprints describe a router/firewall in front of the node, not the node itself. Read the README to understand more: github.com/ViniciusCestarii/…

GitHub - ViniciusCestarii/bitcoin-node-os-fingerprint: Scans publicly reachable Bitcoin nodes with...

Scans publicly reachable Bitcoin nodes with nmap -O to guess their operating system - ViniciusCestarii/bitcoin-node-os-fingerprint

github.com
1
13
1,409
I traced the Bitcoin Core multiprocess binaries (bitcoin-node and bitcoin-wallet) and wrote 3 posts on how it works under the hood. viniciuscestari.dev/posts/in… Turns out I wrote 3 posts to explain one line of C++, because of everything it hides.
13
22
897
ViniciusCestarii retweeted
Vinteum
@Vinteum_orgJul 23
1/ We’re introducing Vinteum’s new fellowship cycle. Four months ago, 12 fellows and 2 grantees began working full-time across Bitcoin Core, wallets, mining, privacy, cryptography, network observability, fuzzing, and protocol research. 🧵 blog.vinteum.org/introducing…
9
41
3
85
8,036
ViniciusCestarii retweeted
Casa21@casavinteumJul 1
A Casa21 agora tem seu próprio site! casa21.vinteum.org/
2
13
2
23
1,488
ViniciusCestarii retweeted
Vinteum
@Vinteum_orgJul 1
A serious website was long overdue. We redesigned vinteum.org to better tell the story of what we’ve been building: funding, training, and supporting open-source Bitcoin developers and researchers in Brazil. Check it out: vinteum.org
5
37
3
84
6,409
Bitcoin Core is splitting its monolith into separate processes. I've spent the last few months studying and contributing to the IPC layer that makes it work, so I wrote up what it is and why it matters. viniciuscestari.dev/posts/in…
3
16
5
60
5,644
ViniciusCestarii retweeted
Casa21@casavinteumMay 28
Acontecendo AGORA! Bitdevs São Paulo na Casa21, não perca nenhum evento, acompanhe e se inscreva em: evento.so/casa21
10
22
544
ViniciusCestarii retweeted
Isaque Franklin
@IsaqueFranklin0May 28
I published a new blog post investigating the field element functions in the first secp256k1 commit. harlock.xyz/the-secp256k1-fi…

The secp256k1 first commit analysis: field element operations

This is a deep dive into the basic workings of the first commit of secp256k1, after it was taken out of Bitcoin Core's code

harlock.xyz
1
13
3
28
3,278
ViniciusCestarii retweeted
Vinteum
@Vinteum_orgMay 29
Our fellow Vinicius has been exploring Bitcoin Core internals and just published a deep dive on what happens from the moment a transaction message reaches a node to when it enters the mempool. If you’ve ever wanted to better understand transaction relay, validation, and mempool acceptance in Bitcoin Core, this is a great read: From TX message to mempool
ViniciusCestarii@VCestariiMay 28
I made a new blog post: what Bitcoin Core does when a peer sends a TX message tracing the full path from message to the mempool. viniciuscestari.dev/posts/fr…
1
16
42
1,961
I made a new blog post: what Bitcoin Core does when a peer sends a TX message tracing the full path from message to the mempool. viniciuscestari.dev/posts/fr…
1
10
3
33
3,026
ViniciusCestarii retweeted
Vinteum
@Vinteum_orgMay 26
Mining decentralization is a big priority for us too. We’re funding @plebhash’s work on Stratum V2, @johnnyasantos’ work on P2Pool V2, and training fellows like @jayrmotta on Mujina and @VCestarii on IPC work that interfaces with mining projects. Looking forward to collaborating with Localhost in yet another area.
localhost research@lclhostresearchMay 26
1/2 Three months ago we announced the resurrection of FIBRE. Today, we take our next step. Localhost Research has established a Mining Unit: a group of contributors working full time on reducing centralization pressures in Bitcoin mining.
2
16
1
41
1,917
ViniciusCestarii retweeted
b10c
@0xB10CApr 15
I measured block propagation and validation duration during the slow-to-validate blocks on Signet event last week. bnoc.xyz/t/block-propagation… The median listening node saw a 160x slowdown in block validation speed. Validation durations for median node: 176ms -> 20s.
1
18
3
51
23,946
ViniciusCestarii retweeted
Vinteum
@Vinteum_orgApr 8
Monitoring the slow blocks demo with our Discord community
2
9
1
33
1,429
ViniciusCestarii retweeted
Hiro | Bitcoisas@BitCoisasApr 2
A verdadeira descentralização exige acessibilidade. 🌲⚙️ ​Com o @getfloresta e o motor SwiftSync, rodar um Full Node de Bitcoin deixa de ser um privilégio de quem tem máquinas potentes. ​Isso é soberania. 🇧🇷
2
8
1
38
1,465
Load more