CVE-2026-44497
CRITICALZEBRA is a Zcash node written entirely in Rust. Prior to zebrad version 4.4.0 and prior to zebra-script version 6.0.0, the fix for CVE-2026-41583 introduced a separate issue due to…
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
Description
ZEBRA is a Zcash node written entirely in Rust. Prior to zebrad version 4.4.0 and prior to zebra-script version 6.0.0, the fix for CVE-2026-41583 introduced a separate issue due to insufficient error handling of the case where the sighash type is invalid, during sighash computation. Instead of returning an error, the normal flow would resume, and the input sighash buffer would be left untouched. In scenarios where a previous signature validation could leave a valid sighash in the buffer, an invalid hash-type could be incorrectly accepted, which would create a consensus split between Zebra and zcashd nodes. This issue has been patched in zebrad version 4.4.0 and zebra-script version 6.0.0.
Affected Products
zebra-scriptzfndzebradzfndDetection & mitigation playbook
Vendor / applianceDetect
Inventory every zfnd zebra-script deployment and check each version against the affected-products list above. Because the exploit targets the running system rather than your application code, also watch for exploitation at the network and runtime layer — O3 flags the exploit behaviour from runtime telemetry and egress traffic even before a vulnerable build is confirmed.
Fix
Apply the zfnd zebra-script security patch or hotfix for CVE-2026-44497 on the affected version, following the vendor advisory for your exact build.
Workarounds
Cut exposure now: restrict the management/admin interface to trusted networks, segment the device, and apply the vendor's recommended configuration mitigations and any WAF/IPS signature. O3's runtime protection blocks the exploit chain at execution, holding the line on unpatched or end-of-life systems until you can patch.
How O3 protects you
O3 detects and blocks CVE-2026-44497 exploitation at runtime: eBPF exploit-chain detection, plus L7 egress monitoring that catches the post-exploitation callback and severs the attacker's outbound channel.
Tailored to CVE-2026-44497. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-44497 being exploited in your environment?
O3's eBPF runtime sensors and L7 egress monitoring detect and block the CVE-2026-44497 exploit chain at execution — protecting unpatched and end-of-life systems until the vendor patch is applied.