# CVE-2026-52738: ZcashFoundation Zebra denial of service via balance overflow in state writer

Source: https://junglewise.ai/threats/cve-2026-52738-zcashfoundation-zebra-denial-of-service-via-balance-overflow-in  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-08-18. Updated: 2026-07-02  
License: CC BY 4.0 with a link back

CVE-2026-52738 · Severity: medium · CVSS 4 · Published 2026-08-18

Zebra is a software implementation used to run nodes on the Zcash cryptocurrency network. A vulnerability has been identified where a specially crafted, valid block can cause the software to crash and fail to restart. This results in a permanent halt of the node, disrupting services such as wallets, exchanges, and mining operations that rely on it.

Technologies: [zebra-state (crates.io)](https://junglewise.ai/threats/technologies/zebra-state), [zebrad (crates.io)](https://junglewise.ai/threats/technologies/zebrad). Vendors: [crates.io](https://junglewise.ai/threats/vendors/crates-io).

## Quick answers

**Is CVE-2026-52738 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-52738 being exploited in the wild.

**How severe is CVE-2026-52738?** Medium severity, with a CVSS score of 4, published 18 August 2026.

**Which products and versions are affected?** zebra-state (crates.io) <= 6.0.0, SEMVER:introduced=0,fixed=7.0.0; zebrad (crates.io) <= 4.4.1, SEMVER:introduced=0,fixed=4.5.0.

**Is there a fix for CVE-2026-52738?** Yes. zebra-state (crates.io): upgrade to 7.0.0 or later; zebrad (crates.io): upgrade to 4.5.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-52738 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-52738?** Check whether you run zebra-state (crates.io) or zebrad (crates.io) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- zebra-state (crates.io): upgrade to 7.0.0 or later

  ```sh
  cargo update -p zebra-state
  ```

- zebrad (crates.io): upgrade to 4.5.0 or later

  ```sh
  cargo update -p zebrad
  ```


## Technical details

The vulnerability is an uncaught exception (panic) caused by an integer overflow in the finalized state writer located at zebra-state/src/service/finalized_state/zebra_db/transparent.rs. The component processes all transaction outputs (credits) in a block before processing inputs (debits); a block containing many self-spends to the same address can cause the intermediate balance to exceed the MAX_MONEY supply cap, triggering a panic via .expect(). Because the block is consensus-valid, the node will re-encounter and re-process the same block upon restart, creating a permanent chain halt. An attacker with sufficient ZEC and mining capability can exploit this remotely by mining a malicious block. The issue is fixed in Zebra 4.4.2 (zebrad) and 7.0.0 (zebra-state) by processing credits and debits together per transaction.

## Affected products

- ZcashFoundation zebrad <= 4.4.1
- ZcashFoundation zebra-state <= 6.0.0

## Identifiers

- CVE-2026-52738
- GHSA-w834-cf6p-9m9w

## Timeline

- 2026-05-29: disclosed
- 2026-07-02: advisory

## References

- [https://api.github.com/users/sangsoo-osec](https://api.github.com/users/sangsoo-osec)
- [https://github.com/sangsoo-osec](https://github.com/sangsoo-osec)
- [https://api.github.com/users/sangsoo-osec/gists%7B/gist_id%7D](https://api.github.com/users/sangsoo-osec/gists%7B/gist_id%7D)
- [https://api.github.com/users/sangsoo-osec/repos](https://api.github.com/users/sangsoo-osec/repos)
- [https://avatars.githubusercontent.com/u/129559837?v=4](https://avatars.githubusercontent.com/u/129559837?v=4)
- [https://api.github.com/users/sangsoo-osec/events%7B/privacy%7D](https://api.github.com/users/sangsoo-osec/events%7B/privacy%7D)

## Related threats

- [ZcashFoundation Zebra assertion panic in address book mempool update](https://junglewise.ai/threats/cve-2026-52829-zcashfoundation-zebra-assertion-panic-in-address-book-mempool)
- [ZcashFoundation Zebra process abort via repeated shielded transactions](https://junglewise.ai/threats/cve-2026-52739-zcashfoundation-zebra-process-abort-via-repeated-shielded)
- [Zcash Zebra sync restart poisoning via above-lookahead block](https://junglewise.ai/threats/cve-2026-52737-zcash-zebra-sync-restart-poisoning-via-above-lookahead-block)
- [ZcashFoundation Zebra block suppression via same-header body poisoning](https://junglewise.ai/threats/cve-2026-52736-zcashfoundation-zebra-block-suppression-via-same-header-body)
- [Zcash Zebra consensus divergence via P2SH sigop undercount](https://junglewise.ai/threats/cve-2026-52735-zcash-zebra-consensus-divergence-via-p2sh-sigop-undercount)