CVE-2023-28628 is a medium-severity (CVSS 5.4) CWE-706 vulnerability in lambdaisland:uri. 1 public exploit reference exists, so weaponization risk is real. A fix is available for lambdaisland:uri — see the affected versions and patch details below.
`authority-regex` returns the wrong authority in lambdaisland/uri
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
Exploitation and automatability from CISA’s SSVC triage for CVE-2023-28628.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2023-28628 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,166 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
lambdaisland:uriReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Maven packages — download data is not available via public APIs for these ecosystems.
Description
lambdaisland/uri is a pure Clojure/ClojureScript URI library. In versions prior to 1.14.120 authority-regex allows an attacker to send malicious URLs to be parsed by the lambdaisland/uri and return the wrong authority. This issue is similar to but distinct from CVE-2020-8910. The regex in question doesn't handle the backslash (\) character in the username correctly, leading to a wrong output. ex. a payload of https://example.com\\@google.com would return that the host is google.com, but the correct host should be example.com. Given that the library returns the wrong authority this may be abused to bypass host restrictions depending on how the library is used in an application. Users are advised to upgrade. There are no known workarounds for this vulnerability.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | lambdaisland:uri | all versions | 1.14.120lambdaisland:uri:1.14.120 |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for lambdaisland:uri, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update lambdaisland:uri to 1.14.120 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-28628 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2023-28628 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2023-28628. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
Frequently Asked Questions
Is CVE-2023-28628 in your dependencies?
O3 Security finds CVE-2023-28628 across Maven dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.