01 Record
CVE-2026-48743
Envoy: HTTP/3 to HTTP/1 request smuggling via headers-only request with nonzero Content-Length
HighPUBLISHEDCNA: GitHub_M
CNA base score7.5 CVSS v3.xCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:H/A:N
02 Description
Envoy: HTTP/3 to HTTP/1 request smuggling via headers-only request with nonzero Content-Length
03 Exploitation and scoring
- Exploitation
- Public exploit code exists. CISA's assessment records a public proof of concept. That is not a report of exploitation in the wild.
- SSVC decision
- ExploitationpocPublic proof-of-concept exploit code exists. Not a report of exploitation in the wild.
- AutomatablenoAt least one step from reconnaissance to exploitation cannot be reliably automated.
- Technical ImpactpartialSuccessful exploitation gives limited control of the vulnerable component.
- EPSS probability
- 0.29% probability of exploitation activity in the next 30 days.
- EPSS percentile
- Equal to or higher than the score of 22.2% of scored records. A rank, not a probability.
- NVD base score
- 7.5 (CVSS v3.x), scored by the NVD independently of the CNA.
- NVD CVSS vector
- CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:H/A:N
- NVD analysis status
- Analyzed. NVD last modified this record on 2026-10-25.
- Red Hat severity
- Important. Red Hat's rating for its own products, not a CVSS rating.
Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.
04 Metadata
- Published
- 2026-06-26 17:34Z4 MO AGO
- Last updated
- 2026-06-29 15:20Z4 MO AGO
- Reserved
- 2026-05-22
- Assigning CNA
- GitHub_M
- Record state
- PUBLISHED
- Severity
- High (CVSS 7.5)
- CNA CVSS vector
- CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:H/A:N
- Weaknesses
- CWE-444Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')Base
- Data version
- 5.2
- Document digest
- 29bc0f61a39fe82722f15367f90c15f8974adbbd04d1bc0a0de869b5ad46c6dd
05 Affected products
VendorProductVersionsPlatforms