How severe is CVE-2021-38157?

CVE-2021-38157 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2021-38157 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (62nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-38157?

CVE-2021-38157 affects Leostream Connection Broker. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-38157?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-38157 published?

CVE-2021-38157 was published on 2021-08-06 and last updated on 2026-06-17.

CVE-2021-38157

CVE-2021-38157 is a medium-severity vulnerability in Leostream Connection Broker with a CVSS 3.x base score of 6.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-79.

Key facts

Severity: Medium (CVSS 3.x base score 6.1)
CVSS v2: 4.3
EPSS exploit prediction: 1% (62nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Leostream Connection Broker
Published: 2021-08-06
Last modified: 2026-06-17

Description

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

Frequently asked questions

What is CVE-2021-38157?: 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
How severe is CVE-2021-38157?: CVE-2021-38157 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2021-38157 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (62nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-38157?: CVE-2021-38157 affects Leostream Connection Broker. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-38157?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-38157 published?: CVE-2021-38157 was published on 2021-08-06 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:leostream:connection_broker:*:*:*:*:*:*:*:*

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