How severe is CVE-2021-35666?

CVE-2021-35666 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2021-35666 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (65th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-35666?

CVE-2021-35666 affects Oracle Http Server. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-35666?

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

When was CVE-2021-35666 published?

CVE-2021-35666 was published on 2021-10-20 and last updated on 2026-06-17.

CVE-2021-35666

CVE-2021-35666 is a medium-severity vulnerability in Oracle Http Server with a CVSS 3.x base score of 5.9. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: Medium (CVSS 3.x base score 5.9)
CVSS v2: 7.1
EPSS exploit prediction: 1% (65th percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Oracle Http Server
Published: 2021-10-20
Last modified: 2026-06-17

Description

Vulnerability in the Oracle HTTP Server product of Oracle Fusion Middleware (component: OSSL Module). The supported version that is affected is 11.1.1.9.0. Difficult to exploit vulnerability allows unauthenticated attacker with network access via HTTPS to compromise Oracle HTTP Server. Successful attacks of this vulnerability can result in unauthorized access to critical data or complete access to all Oracle HTTP Server accessible data. CVSS 3.1 Base Score 5.9 (Confidentiality impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N).

Frequently asked questions

What is CVE-2021-35666?: Vulnerability in the Oracle HTTP Server product of Oracle Fusion Middleware (component: OSSL Module). The supported version that is affected is 11.1.1.9.0. Difficult to exploit vulnerability allows unauthenticated attacker with network access via HTTPS to compromise Oracle HTTP Server. Successful attacks of this vulnerability can result in unauthorized access to critical data or complete access to all Oracle HTTP Server accessible data. CVSS 3.1 Base Score 5.9 (Confidentiality impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N).
How severe is CVE-2021-35666?: CVE-2021-35666 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2021-35666 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (65th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-35666?: CVE-2021-35666 affects Oracle Http Server. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-35666?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-35666 published?: CVE-2021-35666 was published on 2021-10-20 and last updated on 2026-06-17.

References

https://www.oracle.com/security-alerts/cpuoct2021.html

Affected products (1)

cpe:2.3:a:oracle:http_server:11.1.1.9.0:*:*:*:*:*:*:*

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