How severe is CVE-2011-4968?

CVE-2011-4968 has a CVSS 3.x base score of 4.8, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2011-4968 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (89th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2011-4968?

CVE-2011-4968 primarily affects F5 Nginx. In total, 11 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2011-4968?

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

When was CVE-2011-4968 published?

CVE-2011-4968 was published on 2019-11-19 and last updated on 2026-06-16.

CVE-2011-4968

CVE-2011-4968 is a medium-severity vulnerability in F5 Nginx with a CVSS 3.x base score of 4.8. 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 3.x base score 4.8)
CVSS v2: 5.8
EPSS exploit prediction: 4% (89th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: F5 Nginx
Published: 2019-11-19
Last modified: 2026-06-16

Description

nginx http proxy module does not verify peer identity of https origin server which could facilitate man-in-the-middle attack (MITM)

Frequently asked questions

What is CVE-2011-4968?: nginx http proxy module does not verify peer identity of https origin server which could facilitate man-in-the-middle attack (MITM)
How severe is CVE-2011-4968?: CVE-2011-4968 has a CVSS 3.x base score of 4.8, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2011-4968 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (89th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2011-4968?: CVE-2011-4968 primarily affects F5 Nginx. In total, 11 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2011-4968?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2011-4968 published?: CVE-2011-4968 was published on 2019-11-19 and last updated on 2026-06-16.

References

Affected products (11)

cpe:2.3:a:f5:nginx:0.7.61:*:*:*:*:*:*:*
cpe:2.3:a:f5:nginx:0.7.62:*:*:*:*:*:*:*
cpe:2.3:a:f5:nginx:0.7.64:*:*:*:*:*:*:*
cpe:2.3:a:f5:nginx:0.7.65:*:*:*:*:*:*:*
cpe:2.3:a:f5:nginx:0.7.66:*:*:*:*:*:*:*
cpe:2.3:a:f5:nginx:0.8.33:*:*:*:*:*:*:*
cpe:2.3:a:f5:nginx:0.8.35:*:*:*:*:*:*:*
cpe:2.3:a:f5:nginx:0.8.36:*:*:*:*:*:*:*
cpe:2.3:a:f5:nginx:0.8.40:*:*:*:*:*:*:*
cpe:2.3:a:f5:nginx:1.2.6:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*

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