SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityDeferred

CVE-2026-52731

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.

MEDIUM 6.5EPSS 0.53%

Does this matter?

Lower severity and a low EPSS score (0.53%). Track it; it rarely justifies an emergency change on its own.

Description

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.

CVSS 3.1
6.5 MEDIUMCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
EPSS
0.53% probability · 45th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-248
Source
security-advisories@github.com
EPSS trend
0%3%5%26 October 2026: 0.53%26 October 202626 October 2026

EPSS 0.5% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.