CVE-2026-90937
CVE-2026-90937 is a critical-severity vulnerability with a CVSS 3.x base score of 9.9. 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-93.
Key facts
- Severity: Critical (CVSS 3.x base score 9.9)
- CVSS v4: 9.4
- EPSS exploit prediction: 0% (18th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-93
- Published:
- Last modified:
Description
froxlor versions before 2.2.5 fail to validate newline characters in subdomain redirect URLs, allowing authenticated customers to inject arbitrary nginx or Apache configuration directives. Attackers can supply URLs containing literal newlines that are written verbatim into vhost config files during cron rebuild, enabling web server configuration corruption, denial of service, or hijacking of HTTP responses across hosted domains.
Frequently asked questions
- What is CVE-2026-90937?
- froxlor versions before 2.2.5 fail to validate newline characters in subdomain redirect URLs, allowing authenticated customers to inject arbitrary nginx or Apache configuration directives. Attackers can supply URLs containing literal newlines that are written verbatim into vhost config files during cron rebuild, enabling web server configuration corruption, denial of service, or hijacking of HTTP responses across hosted domains.
- How severe is CVE-2026-90937?
- CVE-2026-90937 has a CVSS 3.x base score of 9.9, rated critical severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability low.
- Is CVE-2026-90937 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (18th percentile), an estimate of the probability of exploitation in the next 30 days.
- How do I fix CVE-2026-90937?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
- When was CVE-2026-90937 published?
- CVE-2026-90937 was published on 2026-09-14 and last updated on 2026-09-16.
References
- https://github.com/froxlor/froxlor/security/advisories/GHSA-c3p2-mj7v-5mrc
- https://www.vulncheck.com/advisories/froxlor-before-2.2.5-nginx-apache-configuration-injection-via-subdomain-redirect-url
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