CVE-2026-123557 json
Zebra zebrad before 7.0.0 Reachable Assertion DoS via Peer Disconnection
published 20d ago modified yesterday also EUVD-2026-119442 , GHSA-6v36-c42v-v98p
Unreviewed: the maintainers' own advisory
Published by the maintainers on their GitHub repository ZcashFoundation/zebra. GitHub has not reviewed it into the GitHub Advisory Database, so the affected packages and versions are the maintainers' word. Read the full advisory on GitHub.
- cvss
- 5.9
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 23%
- public exploits
- 0
- none known
Summary
ZcashFoundation Zebra zebrad before 7.0.0 contains a reachable assertion race condition that allows unauthenticated remote peers to abort the node by triggering disconnection during a blocked outbound send. Malicious peers can return empty FindBlocks or FindHeaders replies and stop reading their socket, dropping an unresolved MustUseClientResponseSender and terminating syncing nodes.
Patch / fix
- ZcashFoundation zebra 7.0.0
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- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- yesterday
Exploit prediction
0.31% chance of exploitation in the next 30 days, higher than 23% of all scored CVEs (FIRST EPSS, 2026-11-11).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 8.2 | CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N |
| CNA | 3.1 | 5.9 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H |
| CNA | 4.0 | 8.2 | CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
Affected products
- ZcashFoundation zebra
Classification
- Weakness
-
- CWE-617 Reachable Assertion
References
-
github.com
/ZcashFoundation/zebra/security/advisories/GHSA-6v36-c42v-v98p
vendor-advisory, advisory
-
vulncheck.com
/advisories/zebra-zebrad-before-7.0.0-reachable-assertion-dos-via-peer-disconnection
third-party-advisory
Sources
- CVE List CVE-2026-123557
- NVD CVE-2026-123557
- Maintainer advisory GHSA-6v36-c42v-v98p
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.
The maintainers of ZcashFoundation/zebra published their own advisory on GitHub. Reviewed sources take precedence over it.