DigiByte v9.26.0-rc27 Release Notes

WARNING: This is a TESTNET-ONLY release. DO NOT use on mainnet.

Development Branch: https://github.com/DigiByte-Core/digibyte/tree/feature/digidollar-v1

Join the Developer Chat: https://app.gitter.im/#/room/#digidollar:gitter.im

⚠️ TESTNET RESET — READ THIS FIRST

RC27 resets DigiDollar testnet to testnet20.

This is not the same chain as RC19–RC26. The old testnet (testnet19, port 12033) is retired.

• Old testnet: testnet19 — port 12033 (RC19–RC26)
• New testnet: testnet20 — port 12034 (RC27+)
• Same default RPC port: 14025
• Oracle consensus: 6-of-11
• Oracle bundle format: MuSig2 aggregate signing (v0x03)

🚨 ORACLE OPERATORS: KEEP YOUR WALLETS AND KEYS

DO NOT delete your testnet19 directory. Your oracle wallet contains your private and public keys — you need to copy it into the new testnet20 directory. Your oracle keypair does not change between testnet resets. Only the chain data resets.

What operators and testers need to do

1. Stop your RC26 node
2. Back up your old testnet19 directory — do NOT delete it
3. Install RC27
4. Start RC27 once so it creates testnet20
5. Stop RC27
6. Copy your oracle wallet from testnet19 into testnet20:

   cp -r ~/.digibyte/testnet19/wallets/oracle ~/.digibyte/testnet20/wallets/

7. Start RC27 again and verify your wallet/oracle loads correctly

Your oracle public key and private key remain the same — only the chain resets.

Fast migration example

digibyte-cli -testnet stop
mv ~/.digibyte/testnet19 ~/.digibyte/testnet19.backup
# replace binaries with RC27

digibyted -testnet -daemon
# stop once testnet20 is created if you need to copy wallets
digibyte-cli -testnet stop

cp -r ~/.digibyte/testnet19.backup/wallets/oracle ~/.digibyte/testnet20/wallets/

digibyted -testnet -daemon

If you are an oracle operator:

digibyte-cli -testnet loadwallet "oracle"
digibyte-cli -testnet -rpcwallet=oracle startoracle <your_oracle_id>

🔑 Oracle Operators

Oracle auto-start behavior from prior releases still applies:

• Unencrypted wallets: oracle starts automatically when wallet loads
• Encrypted wallets: oracle starts automatically after walletpassphrase

If auto-start does not trigger for any reason, use the manual startoracle command above.

What's New in RC27

RC27 is the testnet reset + MuSig2 rollout release for DigiDollar oracle signing.

1. Testnet reset to testnet20

RC27 starts a fresh DigiDollar testnet on testnet20 while keeping the existing testnet genesis/magic-byte family intact.

What changed:

• data directory moved from testnet19 → testnet20
• default testnet P2P port moved from 12033 → 12034
• testnet oracle peer endpoints were updated to match the new port

What did not change for this reset:

• no new genesis block for this RC27 reset path
• no new testnet magic bytes for this RC27 reset path

2. Oracle consensus updated to 6-of-11

Mainnet/testnet oracle configuration now uses the real 11-operator set with 6-of-11 consensus.

This replaces the prior smaller testnet quorum model and gives the network better operator redundancy while still being practical for coordinated signing.

3. MuSig2 aggregate signing (v0x03)

RC27 rolls DigiDollar oracle bundles onto MuSig2 aggregate signatures.

That means:

• participating oracle signers contribute nonces and partial signatures
• signatures are aggregated into a single compact Schnorr signature
• bundle validation follows the aggregate-signature path for v0x03 oracle bundles

4. Security: sendoracleprice RPC removed

The sendoracleprice RPC has been permanently removed. This RPC allowed manual injection of arbitrary oracle prices, which is a security vulnerability — oracle prices must only come from live exchange data. Oracles now exclusively fetch prices from Binance, KuCoin, Gate.io, HTX, CoinGecko, and Crypto.com.

5. Bug fixes

Bug #24 — Multi-pass UTXO consolidation for large mints

Large mints could fail when wallet UTXOs were fragmented. Fixed with multi-pass consolidation.

Bug #25 — False-positive lock-height rejection for aged mints

Mints created many blocks ago could be incorrectly rejected during validation. Fixed.

Bug #26 — Oracle block_height preservation and price_source in RPC

Local oracle block_height was not preserved correctly, and getalloracleprices now includes price_source.

Bug #27 — DD change conservation in transfers

Sub-dollar DD change was silently lost during transfers. Fixed with mandatory DD change output.

Bug #29 — Dandelion++ ABBA deadlock (PR #394, JohnnyLawDGB)

A classic ABBA mutex deadlock in CheckDandelionEmbargoes could cause the node to hang under sustained transaction relay load. Thread A held m_dandelion_embargo_mutex and tried to acquire m_nodes_mutex, while Thread B held m_nodes_mutex and tried to acquire m_dandelion_embargo_mutex. Fixed by eliminating the lock-order inversion.

Bug #33 — Mint tooltip limits and silent decimal truncation

The Qt wallet mint dialog showed incorrect tooltip limits for the mint amount field, and amounts with more than 2 decimal places were silently truncated rather than rejected with a clear error message. Both issues are now corrected.

6. MuSig2 signing — three critical fixes

• Nonce participant mismatch: Aggregated all 11 keys but only 6 signed. Fixed: TrimNoncesToThreshold() trims to exactly min_signers before aggregating nonces.
• Message hash mismatch: Signer hashed (epoch, price, ts), verifier hashed (price, ts). Fixed: ComputeOracleBundleHash() now includes epoch.
• Bundle value drift: Miner used GetTime(), signer used consensus timestamp. Fixed: Orchestrator stores signed values via SetSignedValues(), miner retrieves them.

Phase 3 gates have been removed entirely — MuSig2 is always active from genesis, with automatic v0x02 fallback when signing sessions are not ready.

7. Oracle bundle / consensus hardening

The RC27 line also carries the broader MuSig2 implementation work:

• secp256k1 MuSig2 module integration
• MuSig2 signing session/orchestrator work
• oracle bundle serialization/deserialization support for v0x03
• expanded unit coverage for activation, bundle handling, aggregation, mining, net processing, and orchestration

8. Fuzz marathon — 208 targets, zero real bugs

RC27 includes a comprehensive fuzz testing marathon covering all DigiDollar consensus, oracle, MuSig2, Dandelion++, Odocrypt, and multi-algorithm PoW code paths. 208 formal fuzz targets, all passing. OOM issues in DD validation harnesses fixed with strategy selector pattern.

9. Post-Quantum Cryptography plan

RC27 includes documentation for DigiByte's post-quantum cryptography roadmap:

• Full industry PQC landscape analysis (NIST standards, other chains' approaches)
• Two-phase migration strategy for DigiByte and DigiDollar
• Assessment of Taproot/P2TR output vulnerability to quantum key recovery

These are documentation-only commits — no consensus changes.

Test Suite

Full RC27 validation: all C++ unit tests passing, 23 DigiDollar functional tests passing, and 208 fuzz targets all passing.

Commits Since RC26

e57faf7349 Restore production testnet oracle keys for RC27 deployment
b909fe69b0 Remove problematic oracle fuzz targets pending debugging
4d978374cf Remove sendoracleprice remnants from client.cpp and init.cpp
3f5040066c Fix 4 unit test failures for RC27
303be240db Remove Phase 3 gates — MuSig2 is always active, v0x02 fallback allowed
79036fb2d5 Fix MuSig2 signing/verification mismatch — three critical bugs
2176161f4b SECURITY: Remove sendoracleprice RPC — fake price injection vulnerability
26dcdde79a Phase 3: skip oracle bundle when MuSig2 session not ready
fea8df08bb Phase 3 fallback: use Phase 2 bundles when MuSig2 session not ready
f29b689119 Threshold MuSig2: recompute key aggregation for signing subset
0d1f8ca39c Fix v0x03 bitmap sizing: use nOracleTotalOracles, not max participant ID
0f2a960a56 Fix P2P message name overflow: 'oramusignonce' was 13 chars (max 12)
f837036ca2 Fix MuSig2 session timeout: creation_height was set to epoch instead of block height
c8519a73a6 CRITICAL: Wire up MuSig2 signing orchestrator at startup + P2P ingestion
b9a50f78a3 MuSig2: multi-signer sessions + orchestrator-driven block assembly
fb8a602d2c oracle: wire MuSig2 P2P nonce/partial-sig ingestion into signing sessions
1fb3c8c0e2 doc: update RC27 release notes with Bug #29, Bug #33, PQC plan, and full commit list
a7f23b9cc3 Merge pull request #394 from JohnnyLawDGB/fix/dandelion-abba-deadlock
216fb8c364 fix: resolve Dandelion++ ABBA deadlock in CheckDandelionEmbargoes (Bug #29)
8c92bfdd63 fix: Bug #33 — wrong mint tooltip limits + silent decimal truncation
11cca7de0f Fix PQC landscape: DGB HAS Taproot deployed, P2TR outputs are vulnerable
458b0fe9de PQC Plan v2.0: Add full industry landscape and revised two-phase strategy
eec83c39c0 Add Post-Quantum Cryptography plan for DigiByte and DigiDollar
bb929f5d86 test: fix Phase 2 test compatibility with RC27 Phase 3 active from genesis
f605fcd476 fix: add missing musig2 headers to fuzz targets and update redteam tests for RC27 6-of-11
1efb39d5d0 RC27: Make regtest MuSig2 active and remove staged Phase3 gating
ecd86c0abc migrate regtest musig2 phase3 to genesis
74f5a60313 doc: add RC27 release notes for testnet20, 6-of-11 and MuSig2
3281f9a3f0 net: bump testnet directory and P2P port for reset
fa830acdf6 Remove phase3 gate for MuSig2 on main/test and update 6-of-11 oracle assumptions
a5cda93a73 Set main/test oracle consensus to 6-of-11 before Musig2 merge
3d66a1bac0 docs: record latest musig2 phase3 targeted validation pass
36f93eea38 docs: add fresh musig2 hardening evidence pass
b39e64b85e docs: correct musig2 harness validation evidence
0ae984aafa docs: record latest oracle phase2 targeted validation pass
05c0cecd88 docs: add v0x03 aggregate bundle flow validation evidence
154855456a musig2: harden oracle-id bounds in session rounds
8854bc0e7c test: tighten v03 mining bundle bitmap assertion
5cd1419d91 musig2: mark v03 decode version and strengthen bundle tests
699b653963 oracle: enforce exact v0x03 payload size on deserialize
961232c71e docs: add focused MuSig2 hardening regression evidence
e4d65465d8 test: fix oracle functional args for current node options
44236af8b2 docs: fold bitmap-width fix and targeted sanity rerun into MuSig2 status
82e91744ae musig2: pad participation bitmap to network oracle width
75efad3400 docs: finalize MuSig2 Wave 3 status and validation snapshot
16fa01adb3 test: seed coinbase in oracle phase2 pending-message tests
7c00520813 fix: remove regtest<=testnet ordering check (regtest Phase3 intentionally high)
43802ba4d7 musig2 wave3: decode v03 participants and add lifecycle cleanup tests
4fb205534a docs: update MUSIG2_SPRINT_STATUS — Wave 2 complete, 41 commits, 2129 tests pass
1af03dd9c2 fix: bump regtest Phase3 height to 100000 to avoid Phase2 test interference
e0aa6ac567 fix: resolve all MuSig2 test failures — 113 tests passing
9535dfb144 fix: update MuSig2 test expectations to match actual chainparams and v0x03 behavior
fb07aa61fe fix: disable test_v03_messages_decoded_from_bitmap (Wave 3 feature)
088d2fa190 fix: resolve all MuSig2 Wave 2 compile and link errors
8e07be9aff test: add Wave 2 MuSig2 integration tests and build wiring
648b937251 feat: wire MuSig2 v0x03 into bundle manager, session, and build system
193368ccaf feat: add MuSig2 orchestrator, session manager, and participation tracking
02cd12c1c2 test: add Phase3 bundle version activation boundary coverage
bad7399018 consensus: enforce oracle bundle v0x03 at Phase3 boundary
4cf35e42cd consensus: set DigiDollar Phase3 activation heights by network
10521086b2 test: add MuSig2 orchestration coverage for bundle manager
5727481711 oracle: add block-tick MuSig2 session orchestration hooks
e2660aba50 fix: use magic-byte validation for pubnonces instead of serialize
7e4e314b71 test: add MuSig2 net processing message coverage
6b1745c4e9 net: handle MuSig2 nonce and partial signature p2p messages
ba7c268211 test: add MuSig2 P2P message tests and 6 fuzz targets
70f25fb5c9 feat: add MuSig2 P2P message enums, NetMsgType strings, GetHash impls, aggregator cache ctor
e5b8711ab7 fix: remove duplicate v0x03 handler in ExtractOracleBundle
4579902c7a build: add musig2_bundle_creation_tests to unit test target
dadcfdace7 build: include musig2_bundle_manager_tests in unit test target
1b0b00a59b test: add MuSig2 bundle manager v0x03 round-trip coverage
adcdc8789e oracle: add v0x03 MuSig2 script create/extract handling
e7d63332b0 test: add v0x03 MuSig2 bundle creation/extraction tests (TDD)
b14620a080 security: use memory_cleanse for secnonce zeroing in MuSig2SigningSession
ef032561ad feat: implement MuSig2OracleAggregator
16f85ca6bc feat: add MuSig2OracleAggregator header (bitmap + key aggregation interface)
c2b058ed17 test: add MuSig2OracleAggregator tests (TDD — tests before implementation)
391a0481d4 build: add MuSig2SigningSession to build system
b792f97090 feat: implement MuSig2SigningSession state machine
2828259a2e feat: add MuSig2SigningSession header (state machine interface)
234002e5b1 test: add MuSig2SigningSession state machine tests (TDD — tests before implementation)
d98a0028a0 fix: correct SignSchnorr API usage in musig2_basic_tests
5e4e033172 chore: re-apply DGB cosmetic changes to secp256k1 v0.6.0
867753de8c build: update secp256k1 subtree to v0.6.0 (adds MuSig2 module)
45e86f6231 test: add MuSig2 basic crypto tests (TDD — tests before implementation)
d8140c6df0 feat: add nDigiDollarPhase3Height to consensus params
be7dddfee9 feat: implement v0x03 serialization/deserialization in oracle.cpp
1a427d25c5 feat: add v0x03 MuSig2 data structures to COracleBundle
9ae376fb37 test: add v0x03 MuSig2 bundle format tests (TDD first)
7a773869c9 docs: add FUZZ_MARATHON_COMPLETE — Phase 4 final delivery, all targets passing, OOM fixed & validated
621ef8bd47 docs: add FUZZ_PHASE4_FINAL_REPORT — Phase 4 regression complete, all targets validated
e6b8352f59 docs: add Phase 4 final completion report — all targets passing, strategy selector OOM fix validated
4e08300f32 docs: add FUZZ_FINAL_STATUS with OOM fix validation and CI recommendations
102f1f2348 fix: add strategy selectors to DD fuzz targets to prevent OOM under ASan
b2563fa9d5 fix: add strategy selectors to DD fuzz targets to prevent OOM
127ff3bdfa docs: add FUZZ_MARATHON_FINAL.md comprehensive regression report
a18b8283bb docs: fuzz test suite completion summary — 208 targets, all phases complete, zero real bugs
65b96a8cec fix: reduce harness loop bounds and buffer sizes in DD validation fuzz targets to prevent OOM
f5ff6108ea docs: add comprehensive Fuzz Completion Report for March 28 marathon
80ef20dee9 fuzz: add Phase 2A difficulty clamping harness
19934c5b06 fuzz: add Phase 2A block algo routing harness
0a16255fe0 fuzz: finalize Dandelion stem relay target
97b120cb5d fuzz: add Phase 2A proof-of-work all-algo harness
5785bd4de5 fuzz: add Dandelion epoch rotation target
86386813a7 fuzz: add Phase 2A local target adjustment harness
1edcf535ce fuzz: add Phase 2A algo work factor harness
070bc6f79f fuzz: add Dandelion stem relay target
1ddaad38ec fuzz: add Phase 2A algorithm selection harness
0a7d3a4f13 fuzz: add Dandelion routing table target
edcdd2aaa5 fuzz: add Odocrypt Keccak-P[800] finisher target
c2c03b9fee fuzz: add Odocrypt key schedule generation target
e6e8eb179b fuzz: add Phase 2A multishield era transition harness
96f8def5b7 fuzz: add standalone Odocrypt cipher target
3db8c4301a fuzz: add Phase 2A multishield v4 harness
3f6d48ef0b fix: prevent integer overflow in mint validation ratio calculation
feedff58b9 fix: prevent double-to-int64 overflow in ERR GetRequiredDDBurn
c0f9990286 fix: prevent integer overflow in DCA CalculateSystemHealth
5690d0a874 fuzz: add DigiDollar integer math and price conversion fuzz targets
97b54647fc fuzz: add deep DigiDollar validation pipeline fuzz targets
2e127be21a fix: prevent signed integer overflow in CalculateHealthRatio
b1cec14a04 fuzz: add DigiDollar script fuzz targets
9bb12245fa fuzz: add DigiDollar health system fuzz targets
96f6eea39c fuzz: add DigiDollar transaction builder fuzz targets
6edc6a091d fuzz: add DigiDollar logic fuzz targets
84eaae474e fuzz: add DigiDollar consensus fuzz targets
7f75c95451 fuzz: add DigiShield difficulty era fuzz targets
ea6d9fdf7f fuzz: add Dandelion++ privacy fuzz targets
509f3557d1 fuzz: add Odocrypt cipher fuzz targets
8a7a2648f7 fuzz: add multi-algorithm PoW fuzz targets
49eab852b4 fuzz: fix utxo_snapshot chain params initialization
cf91629144 fuzz: register DigiDollar/Oracle RPC commands in fuzz allowlist
ce1a016f02 fuzz: fix mini_miner_selection to use ALGO_SCRYPT for block template
be075b6fc3 fuzz: fix tx_pool Finish() to use ALGO_SCRYPT for block assembly
ff68264fc1 fuzz: fix stale block time comment in versionbits (10min -> 15sec)
f580f4af25 fuzz: fix package_eval outpoints_value for DGB Period I reward
3e9087dc09 fuzz: fix tx_pool SUPPLY_TOTAL for DGB Period I reward (72000 COIN)
e7f4db2aa8 fuzz: fix pow target phashBlock null pointer and add multi-algo coverage
0728db489a fuzz: fix integer target CompressAmount assertion for DGB 21B supply
306d8fdf67 fix: resolve process_message fuzz target crash from multi-algo PoW
755eb11e5e docs: validated byte-exact sizes, verified MuSig2 uses standard schnorrsig_verify
603746d4db docs: critical findings from code audit — signature hash change + epoch rotation
bd424a0c45 docs: add scaling analysis, variable-length bitmap, cache strategy
ae07aa083c docs: highlight linear scaling flaw in oracle bundle sizes
ff1dc1a785 docs: add MuSig2 oracle bundle implementation plan
acb7a09de4 version: bump to v9.26.0-rc27, update wallet image
46a78fd207 oracle: add ChopperBrian as oracle 10 (testnet)
53bbdd0065 oracle: add Ogilvie as oracle 9 (testnet)
611f372a9e consensus: upgrade testnet oracle consensus from 5-of-9 to 9-of-15
66b79115f4 test(transfer): add Bug #27 regression tests for sub-dollar DD change conservation
b940bc01bd fix(transfer): always create DD change output to preserve conservation (Bug #27)
918955ba3f fix: implement multi-pass UTXO consolidation for large mints (Bug #24)
8c54d38ea0 fix: preserve on-chain block_height for local oracle and add price_source to getalloracleprices (Bug #26)
59eed4a438 fix: prevent false-positive lock-height-mismatch rejection for aged mints (Bug #25)

What is DigiDollar?

DigiDollar is a USD-pegged stablecoin built natively into DigiByte. It uses an over-collateralized model where users lock DGB to mint DUSD at the current oracle price of DGB.

The world's first truly decentralized stablecoin native on a UTXO blockchain, enabling stable value transactions without centralized control.

DGB becomes the strategic reserve asset (21B max, only ~1.94 DGB per person on Earth). Everything happens inside DigiByte Core wallet. You never give up custody of your private keys. No centralized company, fund or pool. Pure decentralization.

Learn more: https://digibyte.io/digidollar

Oracle Operator Setup

Upgrading from RC26

digibyte-cli -testnet stop
# Replace binary
# Back up/migrate wallet data from testnet19 if needed

digibyted -testnet -daemon
digibyte-cli -testnet loadwallet "oracle"
digibyte-cli -testnet -rpcwallet=oracle startoracle <your_oracle_id>

New Oracle Setup

digibyted -testnet -daemon
digibyte-cli -testnet createwallet "oracle"
digibyte-cli -testnet -rpcwallet=oracle createoraclekey <your_oracle_id>
digibyte-cli -testnet -rpcwallet=oracle startoracle <your_oracle_id>
# Future restarts will auto-start your oracle.

For the complete guide including earlier migration details, see DIGIDOLLAR_ORACLE_SETUP.md.

Current Oracle Operators (Testnet)

Complete RPC Command Reference

DigiDollar Commands (Wallet)

Oracle Commands

Configuration

testnet=1

[test]
digidollar=1
txindex=1
addnode=oracle1.digibyte.io

Note: txindex=1 is enforced at startup for DD-enabled nodes. Make sure it's in the correct section ([test] for testnet, [main] for mainnet). Global placement (above all sections) also works.

Network Information

Downloads

Known Issues

• This is a fresh DigiDollar testnet reset. Operators should expect to migrate wallets manually if they want to preserve old oracle keys.
• As the network warms up, make sure enough oracle operators are online for 6-of-11 participation.

Troubleshooting

"My oracle did not start automatically"

Load the oracle wallet and start it manually:

digibyte-cli -testnet loadwallet "oracle"
digibyte-cli -testnet -rpcwallet=oracle startoracle <your_oracle_id>

"I still see the old chain"

You are probably still looking at testnet19 data. RC27 uses testnet20.

"My peers are on the old testnet port"

RC27 testnet uses 12034. If you hardcoded peers or firewall rules for 12033, update them.

Feedback & Community

• Developer Chat (Gitter): https://app.gitter.im/#/room/#digidollar:gitter.im
• GitHub Issues: https://github.com/DigiByte-Core/digibyte/issues