How severe is CVE-2026-34475?

CVE-2026-34475 has a CVSS 3.x base score of 5.4, 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-2026-34475 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (10th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-34475?

CVE-2026-34475 primarily affects Varnish-software Varnish Enterprise. In total, 13 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2026-34475?

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

Does CVE-2026-34475 have an EU (EUVD) identifier?

Yes. CVE-2026-34475 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-16801.

When was CVE-2026-34475 published?

CVE-2026-34475 was published on 2026-03-27 and last updated on 2026-06-17.

CVE-2026-34475

CVE-2026-34475 is a medium-severity vulnerability in Varnish-software Varnish Enterprise with a CVSS 3.x base score of 5.4. 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-180.

Key facts

Severity: Medium (CVSS 3.x base score 5.4)
EPSS exploit prediction: 0% (10th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-16801
Weakness: CWE-180
Affected product: Varnish-software Varnish Enterprise
Published: 2026-03-27
Last modified: 2026-06-17

Description

Varnish Cache before 8.0.1 and Varnish Enterprise before 6.0.16r12, in certain unchecked req.url scenarios, mishandle URLs with a path of / for HTTP/1.1, potentially leading to cache poisoning or authentication bypass.

Frequently asked questions

What is CVE-2026-34475?: Varnish Cache before 8.0.1 and Varnish Enterprise before 6.0.16r12, in certain unchecked req.url scenarios, mishandle URLs with a path of / for HTTP/1.1, potentially leading to cache poisoning or authentication bypass.
How severe is CVE-2026-34475?: CVE-2026-34475 has a CVSS 3.x base score of 5.4, 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-2026-34475 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (10th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-34475?: CVE-2026-34475 primarily affects Varnish-software Varnish Enterprise. In total, 13 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2026-34475?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-34475 have an EU (EUVD) identifier?: Yes. CVE-2026-34475 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-16801.
When was CVE-2026-34475 published?: CVE-2026-34475 was published on 2026-03-27 and last updated on 2026-06-17.

References

https://vinyl-cache.org/security/VSV00018.html

Affected products (13)

cpe:2.3:a:varnish-software:varnish_enterprise:*:*:*:*:*:*:*:*
cpe:2.3:a:varnish-software:varnish_enterprise:6.0.16:r1:*:*:*:*:*:*
cpe:2.3:a:varnish-software:varnish_enterprise:6.0.16:r10:*:*:*:*:*:*
cpe:2.3:a:varnish-software:varnish_enterprise:6.0.16:r11:*:*:*:*:*:*
cpe:2.3:a:varnish-software:varnish_enterprise:6.0.16:r2:*:*:*:*:*:*
cpe:2.3:a:varnish-software:varnish_enterprise:6.0.16:r3:*:*:*:*:*:*
cpe:2.3:a:varnish-software:varnish_enterprise:6.0.16:r4:*:*:*:*:*:*
cpe:2.3:a:varnish-software:varnish_enterprise:6.0.16:r5:*:*:*:*:*:*
cpe:2.3:a:varnish-software:varnish_enterprise:6.0.16:r6:*:*:*:*:*:*
cpe:2.3:a:varnish-software:varnish_enterprise:6.0.16:r7:*:*:*:*:*:*
cpe:2.3:a:varnish-software:varnish_enterprise:6.0.16:r8:*:*:*:*:*:*
cpe:2.3:a:varnish-software:varnish_enterprise:6.0.16:r9:*:*:*:*:*:*
cpe:2.3:a:vinyl-cache:vinyl_cache:*:*:*:*:*:*:*:*

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