How severe is CVE-2009-2534?

CVE-2009-2534 has a CVSS 2.0 base score of 5.0, rated medium severity.

Is CVE-2009-2534 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 9% (95th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2009-2534?

CVE-2009-2534 primarily affects Realnetworks Helix Server. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2009-2534?

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

When was CVE-2009-2534 published?

CVE-2009-2534 was published on 2009-07-20 and last updated on 2026-06-16.

CVE-2009-2534

CVE-2009-2534 is a medium-severity vulnerability in Realnetworks Helix Server with a CVSS 2.0 base score of 5.0. 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-20.

Key facts

Severity: Medium (CVSS 2.0 base score 5.0)
EPSS exploit prediction: 9% (95th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Realnetworks Helix Server
Published: 2009-07-20
Last modified: 2026-06-16

Description

RealNetworks Helix Server and Helix Mobile Server before 13.0.0 allow remote attackers to cause a denial of service (daemon crash) via an RTSP SETUP request that (1) specifies the / URI or (2) lacks a / character in the URI.

Frequently asked questions

What is CVE-2009-2534?: RealNetworks Helix Server and Helix Mobile Server before 13.0.0 allow remote attackers to cause a denial of service (daemon crash) via an RTSP SETUP request that (1) specifies the / URI or (2) lacks a / character in the URI.
How severe is CVE-2009-2534?: CVE-2009-2534 has a CVSS 2.0 base score of 5.0, rated medium severity.
Is CVE-2009-2534 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 9% (95th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2009-2534?: CVE-2009-2534 primarily affects Realnetworks Helix Server. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2009-2534?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2009-2534 published?: CVE-2009-2534 was published on 2009-07-20 and last updated on 2026-06-16.

References

Affected products (5)

cpe:2.3:a:realnetworks:helix_server:*:*:*:*:*:*:*:*
cpe:2.3:a:realnetworks:helix_server:11.0:*:*:*:*:*:*:*
cpe:2.3:a:realnetworks:helix_server:12.0.0:*:*:*:*:*:*:*
cpe:2.3:a:realnetworks:helix_server_mobile:*:*:*:*:*:*:*:*
cpe:2.3:a:realnetworks:helix_server_mobile:11.0:*:*:*:*:*:*:*

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