How severe is CVE-2018-8040?

CVE-2018-8040 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.

Is CVE-2018-8040 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 9% (94th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-8040?

CVE-2018-8040 primarily affects Apache Traffic 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-2018-8040?

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

When was CVE-2018-8040 published?

CVE-2018-8040 was published on 2018-08-29 and last updated on 2026-06-17.

CVE-2018-8040

CVE-2018-8040 is a medium-severity vulnerability in Apache Traffic Server with a CVSS 3.x base score of 5.3. 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-668.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
CVSS v2: 5.0
EPSS exploit prediction: 9% (94th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-668
Affected product: Apache Traffic Server
Published: 2018-08-29
Last modified: 2026-06-17

Description

Pages that are rendered using the ESI plugin can have access to the cookie header when the plugin is configured not to allow access. This affects Apache Traffic Server (ATS) versions 6.0.0 to 6.2.2 and 7.0.0 to 7.1.3. To resolve this issue users running 6.x should upgrade to 6.2.3 or later versions and 7.x users should upgrade to 7.1.4 or later versions.

Frequently asked questions

What is CVE-2018-8040?: Pages that are rendered using the ESI plugin can have access to the cookie header when the plugin is configured not to allow access. This affects Apache Traffic Server (ATS) versions 6.0.0 to 6.2.2 and 7.0.0 to 7.1.3. To resolve this issue users running 6.x should upgrade to 6.2.3 or later versions and 7.x users should upgrade to 7.1.4 or later versions.
How severe is CVE-2018-8040?: CVE-2018-8040 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2018-8040 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 9% (94th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-8040?: CVE-2018-8040 primarily affects Apache Traffic 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-2018-8040?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2018-8040 published?: CVE-2018-8040 was published on 2018-08-29 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:apache:traffic_server:*:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*

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