Internal bug detected: FinalizeAndExtractPSBT(psbtx_copy, mtx) #32849

1. 
   ekrembal commented at 1:57 pm on July 1, 2025: none

   Is there an existing issue for this?

   • I have searched the existing issues

   Current behaviour

   0bitcoin-cli -testnet4 descriptorprocesspsbt cHNidP8BAF4CAAAAAfrAU8xRZDY7er/kAUGzVtup++LN4otxeOtANj9Tw8xYAAAAAAD9////AeAPlwAAAAAAIlEgmQIRpk7kW78uK6z/DBX37H4Pi4OLy3Fau0pXquQSXLUAAAAAAAEBK4CWmAAAAAAAIlEg5cugS+vKVwm3OSTEr0sIVU/ahEJzIS6iXjsvWNwJ0VUBAwSDAAAAAQhDAUFATOMkSjzzD+7k1AnzZgJ+G+sDZXX5ob0tlQ9mZIseDe73u4fU6SPKdtxve2Wm/mVNrRIP5cPEnkcMv0BJ2iIWgyEWtJa/uuFJh4F8U9WSvgqmbEXHuURDwfdFUTc/nONNI0YZAP/2NCNWAACAAAAAgAAAAIAAAAAAAAAAAAEXILSWv7rhSYeBfFPVkr4KpmxFx7lEQ8H3RVE3P5zjTSNGAAA= "[\"tr([fff63423/86'/0'/0']tpubDDfvptb1GNdu4TRUUNf9bwsFFpHADAmwaB3uoC8ukv5JMsYPzEc3E6yg4w8t49Wq7jtL8LC3VPmuhXoSJxpamWDPfphAz3Fioki3WerwH3Y/0/0)#twc4a4lc\"]"
   1error code: -1
   2error message:
   3Internal bug detected: FinalizeAndExtractPSBT(psbtx_copy, mtx)
   4rpc/rawtransaction.cpp:1986 (operator())
   5Bitcoin Core v29.0.0
   6Please report this issue here: https://github.com/bitcoin/bitcoin/issues
   

   Expected behaviour

   This should give an error maybe stating that the signature inside the final_scriptwitness is an invalid schnorr signature. Please note that the signature inside the psbt uses SIGHASH_SINGLE | ANYONECANPAY flag

   Steps to reproduce

   The same command should work on any local regtest or testnet4.

   Relevant log output

   No response

   How did you obtain Bitcoin Core

   Pre-built binaries

   What version of Bitcoin Core are you using?

   v29.0.0

   Operating system and version

   macOS Sequoia 15.1.1

   Machine specifications

   No response

2. 
   maflcko commented at 5:55 am on July 2, 2025: member

   uploaded to oss-fuzz (https://issues.oss-fuzz.com/issues/429003360) to get a regression range: https://github.com/bitcoin/bitcoin/compare/b000ed5ee54438efb72e190262faeb535489d35d...ac9fa6ec78158e41006d621ee62e44dec0f934c0 (exists since the beginning, when the line was added)
3. maflcko added the label Bug on Jul 2, 2025
4. maflcko added the label RPC/REST/ZMQ on Jul 2, 2025
5. 
   b-l-u-e commented at 7:48 am on July 5, 2025: none

   I can confirm this bug exists in Bitcoin Core v29.0.0. I’ve reproduced it and found the root cause: the CHECK_NONFATAL assertion in src/rpc/rawtransaction.cpp around line 1986 triggers an internal bug when FinalizeAndExtractPSBT encounters invalid Schnorr signatures. The fix is to replace the CHECK_NONFATAL with proper error handling that throws a JSONRPCError with a clear message instead of crashing. I’ll submit a PR with the fix shortly.
6. ?
   user_blocked bitcoin
7. bitcoin deleted a comment on Jul 16, 2025

Contributors
ekrembal maflcko b-l-u-e

Labels
Bug RPC/REST/ZMQ