CVE-2021-38157 json
LeoStream Connection Broker 9.x before 9.0.34.3 allows Unauthenticated Reflected XSS via the /index.pl user parameter.
published 2021-08-06 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-24627
- cvss
- 6.1
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.1%
- EPSS 1.1% chance of exploitation in 30 days, percentile 66%
- public exploits
- 0
- none known
Summary
LeoStream Connection Broker 9.x before 9.0.34.3 allows Unauthenticated Reflected XSS via the /index.pl user parameter. NOTE: This vulnerability only affects products that are no longer supported by the maintainer
Patch / fix
- leostream connection_broker 9.0.34.3
CISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- no
- Technical impact
- partial
- Assessed
- 2 y ago
Exploit prediction
1.12% chance of exploitation in the next 30 days, higher than 66% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- gist.github.com https://gist.github.com/erud1te-sec/5c85924cb78ba85af42e0b7b62a5ec91 referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 3.1 | 6.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N |
| NVD | 2.0 | 4.3 | AV:N/AC:M/Au:N/C:N/I:P/A:N |
Classification
- Weakness
-
- CWE-79 Improper Neutralization of Input During Web Page Generation
References
-
gist.github.com
/erud1te-sec/5c85924cb78ba85af42e0b7b62a5ec91
exploit, third-party-advisory
-
leostream.com
vendor-advisory
-
leostream.com
/resources-2/product-lifecycle/
vendor-advisory
-
dgccpa.com
third-party-advisory
Sources
- CVE List CVE-2021-38157
- NVD CVE-2021-38157
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