CVE-2026-41583: ZcashFoundation zebra · Improper Following of Specification by Caller
Affects ZcashFoundation zebraSource CVE Database V5
Not known to be exploited · CVSS 9.3 Critical · fixed in 4.3.1 : patch ZcashFoundation zebra as a priority.
Data as of 30 Oct 2026, 11:52 UTC
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 20% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 4.3.1, 5.0.2
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:H/SC:N/SI:H/SA:HExploitation evidence
Disclosed: evidence found.
CVE published 8 May 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 30 Oct 2026.
What to do
Upgrade github/ZcashFoundation/zebra to 4.3.1; github/ZcashFoundation/zebra-script to 5.0.2.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| ZcashFoundationzebra | Affected
| Fixed in– |
crates.iogithub/ZcashFoundation/zebrapkg:cargo/github/ZcashFoundation/zebraOther threats | Affected
| Fixed in
|
crates.iogithub/ZcashFoundation/zebra-scriptpkg:cargo/github/ZcashFoundation/zebra-scriptOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
A fix is available and has been released in zebrad version 4.3.1 and zebra-script version 5.0.2. Users and operators of Zebra nodes should upgrade to these versions or later to resolve the vulnerability and prevent consensus splits. Patch status beyond these versions is not explicitly stated but assumed included. No other mitigation actions are indicated.
Description
ZEBRA is a Zcash node written entirely in Rust. Prior to zebrad version 4.3.1 and prior to zebra-script version 5.0.2, after a refactoring, Zebra failed to validate a consensus rule that restricted the possible values of sighash hash types for V5 transactions which were enabled in the NU5 network upgrade. Zebra nodes could thus accept and eventually mine a block that would be considered invalid by zcashd nodes, creating a consensus split between Zebra and zcashd nodes. In a similar vein, for V4 transactions, Zebra mistakenly used the "canonical" hash type when computing the sighash while zcashd (correctly per the spec) uses the raw value, which could also crate a consensus split. This issue has been patched in zebrad version 4.3.1 and zebra-script version 5.0.2.