CVE-2021-43797

Exploitation

Assessed, none found. CISA's assessment recorded neither public exploit code nor evidence of exploitation when it was made.

SSVC decision

• ExploitationnoneCISA recorded no public exploit code and no evidence of exploitation.
• AutomatablenoAt least one step from reconnaissance to exploitation cannot be reliably automated.
• Technical ImpactpartialSuccessful exploitation gives limited control of the vulnerable component.

CISA publishes the decision points, not a final SSVC decision. The decision also depends on mission and well-being impact, which is a property of your deployment rather than of the vulnerability.

EPSS probability

2.88% probability of exploitation activity in the next 30 days.

EPSS percentile

Equal to or higher than the score of 86.3% of scored records. A rank, not a probability.

NVD base score

6.5 (CVSS v3.x), scored by the NVD independently of the CNA.

NVD CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N

NVD analysis status

Modified. NVD last modified this record on 2026-10-08.

Red Hat severity

Moderate. 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.

Published

2021-12-09 00:00Z4 YR AGO

Last updated

2026-10-08 21:13Z20 DAYS AGO

Reserved

2021-11-16

Assigning CNA

GitHub_M

Record state

PUBLISHED

Severity

Medium (CVSS 6.5)

CNA CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N

Weaknesses

• CWE-444Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')Base

Data version

5.2

Document digest

5fbf87d47dc2fc2cf910cebda05d4883a5d330362f2c51d2cc4534f66efee454

• github.comhttps://github.com/netty/netty/security/advisories/GHSA-wx5j-54mm-rqqq
• github.comhttps://github.com/netty/netty/commit/07aa6b5938a8b6ed7a6586e066400e2643897323
• www.oracle.comhttps://www.oracle.com/security-alerts/cpuapr2022.html
• security.netapp.comhttps://security.netapp.com/advisory/ntap-20220107-0003/
• www.oracle.comhttps://www.oracle.com/security-alerts/cpujul2022.html
• lists.debian.org[debian-lts-announce] 20230111 [SECURITY] [DLA 3268-1] netty security updatehttps://lists.debian.org/debian-lts-announce/2023/01/msg00008.htmlmailing-list
• www.debian.orgDSA-5316https://www.debian.org/security/2023/dsa-5316vendor-advisory