How severe is CVE-2026-27585?

CVE-2026-27585 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2026-27585 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (24th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-27585?

CVE-2026-27585 affects Caddyserver Caddy. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-27585?

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

Does CVE-2026-27585 have an EU (EUVD) identifier?

Yes. CVE-2026-27585 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-8539.

When was CVE-2026-27585 published?

CVE-2026-27585 was published on 2026-02-24 and last updated on 2026-06-17.

CVE-2026-27585

CVE-2026-27585 is a medium-severity vulnerability in Caddyserver Caddy with a CVSS 3.x base score of 6.5. 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 6.5)
CVSS v4: 6.9
EPSS exploit prediction: 0% (24th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-8539
Weakness: CWE-20
Affected product: Caddyserver Caddy
Published: 2026-02-24
Last modified: 2026-06-17

Description

Caddy is an extensible server platform that uses TLS by default. Prior to version 2.11.1, the path sanitization routine in file matcher doesn't sanitize backslashes which can lead to bypassing path related security protections. It affects users with specific Caddy and environment configurations. Version 2.11.1 fixes the issue.

Frequently asked questions

What is CVE-2026-27585?: Caddy is an extensible server platform that uses TLS by default. Prior to version 2.11.1, the path sanitization routine in file matcher doesn't sanitize backslashes which can lead to bypassing path related security protections. It affects users with specific Caddy and environment configurations. Version 2.11.1 fixes the issue.
How severe is CVE-2026-27585?: CVE-2026-27585 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2026-27585 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (24th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-27585?: CVE-2026-27585 affects Caddyserver Caddy. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-27585?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-27585 have an EU (EUVD) identifier?: Yes. CVE-2026-27585 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-8539.
When was CVE-2026-27585 published?: CVE-2026-27585 was published on 2026-02-24 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:caddyserver:caddy:*:*:*:*:*:*:*:*

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