CVE-2020-36406 json
uWebSockets 18.11.0 and 18.12.0 has a stack-based buffer overflow in uWS::TopicTree::trimTree (called from uWS::TopicTree::unsubscribeAll).
published 2021-07-01 5 y ago modified 2026-06-17 4 mo ago also EUVD-2020-23934
- cvss
- 8.8
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.5%
- EPSS 1.5% chance of exploitation in 30 days, percentile 74%
- public exploits
- 0
- none known
Summary
uWebSockets 18.11.0 and 18.12.0 has a stack-based buffer overflow in uWS::TopicTree::trimTree (called from uWS::TopicTree::unsubscribeAll). NOTE: the vendor's position is that this is "a minor issue or not even an issue at all" because the developer of an application (that uses uWebSockets) should not be allowing the large number of triggered topics to accumulate
Patch / fix
Exploit prediction
1.52% chance of exploitation in the next 30 days, higher than 74% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- bugs.chromium.org https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=25381 referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 3.1 | 8.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H |
| NVD | 2.0 | 6.8 | AV:N/AC:M/Au:N/C:P/I:P/A:P |
Classification
- Weakness
-
- CWE-787 Out-of-bounds Write
References
-
github.com
/uNetworking/uWebSockets/commit/03fca626a95130ab80f86adada54b29d27242759
patch, third-party-advisory
-
bugs.chromium.org
/p/oss-fuzz/issues/detail?id=25381
exploit, issue-tracking, patch, third-party-advisory
-
github.com
/google/oss-fuzz-vulns/blob/main/vulns/uwebsockets/OSV-2020-1695.yaml
third-party-advisory
Sources
- CVE List CVE-2020-36406
- NVD CVE-2020-36406
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