CVE detail
CVE-2026-1527
ImpactWhen an application passes user-controlled input to the upgrade option of client.request(), an attacker can inject CRLF sequences (\r\n) to: * Inject arbitrary HTTP headers * Terminate the HTTP request prematurely and smuggle raw data to non-HTTP services (Redis, Memcached, Elasticsearch) The vulnerability exists because undici writes the upgrade value directly to the socket without validating for invalid header characters: // lib/dispatcher/client-h1.js:1121 if (upgrade) { header += `connection: upgrade\r\nupgrade: ${upgrade}\r\n` }
Buzz score
Why this CVE is surfacing
This all-time snapshot uses the same composite formula as Trending across a 30-year evidence window, rather than a current rolling window.
Buzz score components · mention 13.9 · diversity 11.5 · KEV 0.0 · OTX 0.0 · PoC 0.0
Why it matters now
Mention timeline
- Total mentions
- 0
- within the 30d window
- Peak daily
- 0
- highest bucket
Evidence
Source links by recency
3 source links · newest first
- https://hackerone.com/reports/3487198hackerone.com
No excerpt available.
Exploithackerone.comMar 12, 2026, 9:16 PM No excerpt available.
Exploitgithub.comMar 12, 2026, 9:16 PM- https://cna.openjsf.org/security-advisories.htmlcna.openjsf.org
No excerpt available.
Vendor Advisorycna.openjsf.orgMar 12, 2026, 9:16 PM
Exploit code
Public exploit repository references
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0 repository references · best confidence N/A · max 0 stars
Related records
Similar CVEs
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