Vulnerability in Encode Starlette
CVE-2026-54282
Starlette is a lightweight ASGI framework/toolkit. Prior to 1.3.0, the HTTP request path is not validated before being used to reconstruct request.url. Because request.url is rebuilt by concatenating {scheme}://{host}{path} and re-parsing the result, a path that does not begin with / (for example @google.com) moves the authority boundary during re-parsing, so request.url.hostname and request.url.netloc become attacker-controlled. Code that reads request.url.hostname (rather than the Host header or scope) can therefore be misled into trusting an attacker-supplied host. This vulnerability is fixed in 1.3.0.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 3.7 (Low). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N.
EPSS exploit prediction
EPSS: 0.003 (17.7th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 18th percentile — 17.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: 0.000
Affected products
- Encode Starlette
- Kludex Starlette — versions < 1.3.0
Weakness classification (CWE)
References
- github.com/Kludex/starlette/security/advisories/GHSA-jp82-jpqv-5vv3 (Mitigation, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-54282?
- CVE-2026-54282 is a low-severity vulnerability in Encode Starlette, classified under Use of Incorrectly-Resolved Name or Reference. CVSS score: 3.7/10. Published 2026-06-22.
- How severe is CVE-2026-54282?
- Low severity. CVSS v3 base score is 3.7 out of 10.