onyx

onyx --cves cve-2023-27491

CVE-2023-27491

MEDPOCEnvoy Proxy
score
<0.1
cvss
5.4
epss
0.9%
published
2023-04-04
kev added
—
first seen

Envoy versions prior to 1.26.0, 1.25.3, 1.24.4, 1.23.6, and 1.22.9 contain a security bypass caused by improper handling of malformed request lines in HTTP/1 services, letting non-compliant requests bypass security policies, exploit requires sending malformed HTTP requests.

Timeline

How this CVE moved toward exploitation. Chart: last 30 days — trend score, EPSS, community mentions per day; hover the event lane.

events2023-04-04 — PublishedP2026-10-21 — Tracked by OnyxT2026-10-21 — Public PoCXscore2026-10-21: score <0.1<0.1epss2026-09-22: epss 0.9%2026-09-23: epss 0.9%2026-09-24: epss 0.9%2026-09-25: epss 0.9%2026-09-26: epss 0.9%2026-09-27: epss 0.9%2026-09-28: epss 0.9%2026-09-29: epss 0.9%2026-09-30: epss 0.9%2026-10-01: epss 0.9%2026-10-02: epss 0.9%2026-10-03: epss 0.9%2026-10-04: epss 0.9%2026-10-05: epss 0.9%2026-10-06: epss 0.9%2026-10-07: epss 0.9%2026-10-08: epss 0.9%2026-10-09: epss 0.9%2026-10-10: epss 0.9%2026-10-11: epss 0.9%2026-10-12: epss 0.9%2026-10-13: epss 0.9%2026-10-14: epss 0.9%2026-10-15: epss 0.9%2026-10-16: epss 0.9%2026-10-18: epss 0.9%2026-10-19: epss 0.9%2026-10-20: epss 0.9%2026-10-21: epss 0.9%0.9%mentions/day0no mentions in 30 days2026-09-22today
  1. Published
  2. Tracked by Onyx
  3. Public PoC

Exploit availability

Public PoC flagged by vulnx; no direct exploit link among the citations.

Weaknesses

CWE-20 CWE-444

References 1