CVE-2026-44498 ZEBRA: Block Validator Undercounts Coinbase and P2SH Sigops
Zebra node accepts invalid blocks due to sigop undercounting, causing network splits and potential denial of service for Zcash users.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-44498?
CVE-2026-44498 is a critical vulnerability in ZcashFoundation zebra, published on 8 May 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
ZEBRA is a Zcash node written entirely in Rust. Prior to version 4.4.0, Zebra's block validator undercounts transparent signature operations against the 20000-sigop block limit (MAX_BLOCK_SIGOPS), allowing it to accept blocks that zcashd rejects with bad-blk-sigops. A miner who produces such a block can split the network: Zebra nodes follow the offending chain while zcashd nodes do not. This issue has been patched in version 4.4.0.
Weakness: CWE-682
Which versions are affected by CVE-2026-44498?
2 open source packages ship an affected version, including zebrad. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
zebrad crates.io | All versions | 4.4.0 |
zebrad crates.io | All versions | 4.4.0 |
Products include Zfnd Zebrad.
How do I fix CVE-2026-44498?
Upgrade zebrad to 4.4.0 or later.
Is CVE-2026-44498 being exploited?
There is no known exploitation of CVE-2026-44498 in the wild and no public exploit code.
Sources
Also known as GHSA-jv4h-j224-23cc.