How severe is CVE-2009-2699?

CVE-2009-2699 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2009-2699 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 14% (96th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2009-2699?

CVE-2009-2699 primarily affects Apache Http Server. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2009-2699?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2009-2699 published?

CVE-2009-2699 was published on 2009-10-13 and last updated on 2026-06-16.

CVE-2009-2699

CVE-2009-2699 is a high-severity vulnerability in Apache Http Server with a CVSS 3.x base score of 7.5. Its EPSS exploit-prediction score of 14% places it in the 96th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-667.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 14% (96th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-667
Affected product: Apache Http Server
Published: 2009-10-13
Last modified: 2026-06-16

Description

The Solaris pollset feature in the Event Port backend in poll/unix/port.c in the Apache Portable Runtime (APR) library before 1.3.9, as used in the Apache HTTP Server before 2.2.14 and other products, does not properly handle errors, which allows remote attackers to cause a denial of service (daemon hang) via unspecified HTTP requests, related to the prefork and event MPMs.

Frequently asked questions

What is CVE-2009-2699?: The Solaris pollset feature in the Event Port backend in poll/unix/port.c in the Apache Portable Runtime (APR) library before 1.3.9, as used in the Apache HTTP Server before 2.2.14 and other products, does not properly handle errors, which allows remote attackers to cause a denial of service (daemon hang) via unspecified HTTP requests, related to the prefork and event MPMs.
How severe is CVE-2009-2699?: CVE-2009-2699 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2009-2699 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 14% (96th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2009-2699?: CVE-2009-2699 primarily affects Apache Http Server. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2009-2699?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2009-2699 published?: CVE-2009-2699 was published on 2009-10-13 and last updated on 2026-06-16.

References

Affected products (2)

cpe:2.3:a:apache:http_server:*:*:*:*:*:*:*:*
cpe:2.3:a:apache:portable_runtime:*:*:*:*:*:*:*:*

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Threat intelligence

Threat-intel indicators referencing this CVE:

222.99.52.202 (ipv4-addr)
41.224.62.206 (ipv4-addr)
218.4.156.254 (ipv4-addr)
171.100.156.38 (ipv4-addr)