CVE-2026-52731 json
ZEBRA: Full node denial of service via non-ASCII LongPollId in getblocktemplate
published 4mo ago modified 2d ago also EUVD-2026-61169 , GHSA-qv2r-v3mx-f4pf
- cvss
- 6.5
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.5%
- EPSS 0.5% chance of exploitation in 30 days, percentile 45%
- public exploits
- 0
- none known
Summary
ZEBRA is a Zcash node written entirely in Rust. Prior to 4.5.0, an attacker authenticated to an enabled Zebra RPC endpoint can terminate zebrad by supplying a getblocktemplate LongPollId containing multi-byte UTF-8 characters. In zebra-rpc/src/methods/types/long_poll.rs, LongPollId::from_str originally checked the input byte length and then sliced fixed byte ranges to parse encoded fields. A slice boundary can land inside a multi-byte character and trigger Rust's byte index is not a char boundary panic. Zebra release builds use panic equals abort, so one malformed authenticated RPC request terminates the entire node process and can be repeated after restart. This issue is fixed in version 4.5.0.
Patch / fix
- crates.io zebra-rpc 8.0.0
- crates.io zebrad 4.5.0
- zfnd zebra 4.5.0
- zfnd zebrad 4.5.0
- zfnd zebra-rpc 8.0.0
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Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 2mo ago
Exploit prediction
0.53% chance of exploitation in the next 30 days, higher than 45% of all scored CVEs (FIRST EPSS, 2026-11-11).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 6.5 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |
| GitHub | 3.1 | 6.5 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| crates.io | zebra-rpc | <8.0.0 |
8.0.0 |
| crates.io | zebrad | <4.5.0 |
4.5.0 |
Affected products
- ZcashFoundation zebra
- ZcashFoundation zebra-rpc
Classification
- Weakness
-
- CWE-248 Uncaught Exception
References
- github.com /ZcashFoundation/zebra/commit/1440b43ca7df59aca948090d45117557b217a6cd
-
github.com
/ZcashFoundation/zebra/security/advisories/GHSA-qv2r-v3mx-f4pf
web
- github.com /ZcashFoundation/zebra/releases/tag/v4.5.0
-
github.com
/ZcashFoundation/zebra
package
-
github.com
/ZcashFoundation/zebra/blob/d4cd662c716382f6397d2a730148025a1ca79fec/Cargo.toml#L305
web
Sources
- CVE List CVE-2026-52731
- GitHub Advisory GHSA-qv2r-v3mx-f4pf
- NVD CVE-2026-52731
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.