CVE-2021-48011 is a high-severity (CVSS 7.5) Path Traversal vulnerability. No vendor fix is recorded yet; mitigation options are listed below.
Servor 1.0.0 through 4.0.2 contains a path traversal vulnerability that allows unauthenticated remote attackers to escape the served root by sending URL-encoded dot segments. Attackers…
Exploitation Status
No confirmed exploitation observed yet
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2021-48011.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
CVE-2021-48011 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.
Where this sits among everything scored
Of 385,987 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.
Description
Servor 1.0.0 through 4.0.2 contains a path traversal vulnerability that allows unauthenticated remote attackers to escape the served root by sending URL-encoded dot segments. Attackers can send %2e%2e/ sequences, which decodeURI() decodes before path.join() in serveStaticFile and serveDirectoryListing, to read arbitrary files and list directories outside the root.
Detection & mitigation playbook
VulnerabilityDetect
Identify every host running the affected component and compare the installed build against the fixed version below — for source-built or distro-packaged software the version string, not a lockfile, is the source of truth (`dpkg -l`, `rpm -q`, or the binary's own `--version`).
Remediation status
No fixed release is recorded for CVE-2021-48011 yet. Track the upstream advisory, and apply the exposure-reduction steps below in the meantime.
Mitigate without a patch
Resolve every user-supplied path to its canonical form and reject anything that escapes the intended directory, and run the component under an account that has no read or write access outside the directory it legitimately serves.
Frequently Asked Questions
Is CVE-2021-48011 in your dependencies?
Find it across , including transitive dependencies.