How severe is CVE-2026-27508?

CVE-2026-27508 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2026-27508 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (5th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-27508?

CVE-2026-27508 primarily affects Smoothwall Smoothwall Express. In total, 13 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2026-27508?

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

Does CVE-2026-27508 have an EU (EUVD) identifier?

Yes. CVE-2026-27508 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-17127.

When was CVE-2026-27508 published?

CVE-2026-27508 was published on 2026-03-30 and last updated on 2026-06-17.

CVE-2026-27508

CVE-2026-27508 is a medium-severity vulnerability in Smoothwall Smoothwall Express 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-79.

Key facts

Severity: Medium (CVSS 3.x base score 5.4)
CVSS v4: 5.1
EPSS exploit prediction: 0% (5th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-17127
Weakness: CWE-79
Affected product: Smoothwall Smoothwall Express
Published: 2026-03-30
Last modified: 2026-06-17

Description

Smoothwall Express versions prior to 3.1 Update 13 contain a reflected cross-site scripting vulnerability in the /redirect.cgi endpoint due to improper sanitation of the url parameter. Attackers can craft malicious URLs with javascript: schemes that execute arbitrary JavaScript in victims' browsers when clicked through the unsanitized link.

Frequently asked questions

What is CVE-2026-27508?: Smoothwall Express versions prior to 3.1 Update 13 contain a reflected cross-site scripting vulnerability in the /redirect.cgi endpoint due to improper sanitation of the url parameter. Attackers can craft malicious URLs with javascript: schemes that execute arbitrary JavaScript in victims' browsers when clicked through the unsanitized link.
How severe is CVE-2026-27508?: CVE-2026-27508 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2026-27508 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (5th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-27508?: CVE-2026-27508 primarily affects Smoothwall Smoothwall Express. In total, 13 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2026-27508?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-27508 have an EU (EUVD) identifier?: Yes. CVE-2026-27508 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-17127.
When was CVE-2026-27508 published?: CVE-2026-27508 was published on 2026-03-30 and last updated on 2026-06-17.

References

Affected products (13)

cpe:2.3:o:smoothwall:smoothwall_express:*:*:*:*:*:*:*:*
cpe:2.3:o:smoothwall:smoothwall_express:3.1:update1:*:*:-:*:*:*
cpe:2.3:o:smoothwall:smoothwall_express:3.1:update10:*:*:-:*:*:*
cpe:2.3:o:smoothwall:smoothwall_express:3.1:update11:*:*:-:*:*:*
cpe:2.3:o:smoothwall:smoothwall_express:3.1:update12:*:*:-:*:*:*
cpe:2.3:o:smoothwall:smoothwall_express:3.1:update2:*:*:-:*:*:*
cpe:2.3:o:smoothwall:smoothwall_express:3.1:update3:*:*:-:*:*:*
cpe:2.3:o:smoothwall:smoothwall_express:3.1:update4:*:*:-:*:*:*
cpe:2.3:o:smoothwall:smoothwall_express:3.1:update5:*:*:-:*:*:*
cpe:2.3:o:smoothwall:smoothwall_express:3.1:update6:*:*:-:*:*:*
cpe:2.3:o:smoothwall:smoothwall_express:3.1:update7:*:*:-:*:*:*
cpe:2.3:o:smoothwall:smoothwall_express:3.1:update8:*:*:-:*:*:*
cpe:2.3:o:smoothwall:smoothwall_express:3.1:update9:*:*:-:*:*:*

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