CVE-2026-104436 json
Zebra before 4.5.0 CPU Amplification via Uncapped getblocks/getheaders Locator Length
published 4mo ago modified 11d ago also EUVD-2026-91446 , GHSA-443g-gwgp-49x4
- cvss
- 3.7
- 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 19%
- public exploits
- 0
- none known
Summary
Zebra before 4.5.0 contains an uncontrolled resource consumption vulnerability that allows remote P2P peers to exhaust blocking-pool threads by sending oversized block locator vectors. Attackers can send getblocks or getheaders messages with up to 65,535 locator hashes, triggering per-hash chain lookups that degrade block validation, RPC, and mempool performance.
Patch / fix
- crates.io zebrad 4.5.0
- crates.io zebra-chain 8.0.0
- ZcashFoundation zebra 4.5.0
- ZcashFoundation zebra-chain 8.0.0
- github.com/ZcashFoundation/zebra@8981a1b commit
- github.com/ZcashFoundation/zebra#10570 pull request
Is CVE-2026-104436 in your dependencies? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- last mo.
Exploit prediction
0.27% chance of exploitation in the next 30 days, higher than 19% of all scored CVEs (FIRST EPSS, 2026-11-09).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 6.3 | CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N |
| CNA | 3.1 | 3.7 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L |
| GitHub | 3.1 | 3.7 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L |
| CNA | 4.0 | 6.3 | CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/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 packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| crates.io | zebrad | <4.5.0 |
4.5.0 |
| crates.io | zebra-chain | <8.0.0 |
8.0.0 |
Affected products
- ZcashFoundation zebra
- ZcashFoundation zebra-chain
Classification
- Weakness
-
- CWE-770 Allocation of Resources Without Limits or Throttling
References
-
github.com
/ZcashFoundation/zebra/pull/10570
web
-
github.com
/ZcashFoundation/zebra/commit/8981a1b95d4807cad99e5bb3b94fc8bc723ac033
web
-
github.com
/ZcashFoundation/zebra/security/advisories/GHSA-443g-gwgp-49x4
vendor-advisory, web
-
vulncheck.com
/advisories/zebra-before-4.5.0-cpu-amplification-via-uncapped-getblocks-getheaders-locator-length
third-party-advisory
-
github.com
/ZcashFoundation/zebra
package
Sources
- CVE List CVE-2026-104436
- GitHub Advisory GHSA-443g-gwgp-49x4
- NVD CVE-2026-104436
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.