Medium 6.5Published Dec 8, 2021

CVE-2021-43797HTTP fails to validate against control chars in header names which may lead to HTTP request smuggling

Updated under an hour ago (Oct 27, 2026, 1:40 AM ET)

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It affects netty and 17 other products. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

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Every CVE for netty

Exploited in the last 30 days

Netty is an asynchronous event-driven network application framework for rapid development of maintainable high performance protocol servers & clients. Netty prior to version 4.1.71.Final skips control chars when they are present at the beginning / end of the header name. It should instead fail fast as these are not allowed by the spec and could lead to HTTP request smuggling. Failing to do the validation might cause netty to "sanitize" header names before it forward these to another remote system when used as proxy. This remote system can't see the invalid usage anymore, and therefore does not do the validation itself. Users should upgrade to version 4.1.71.Final.

CVSS: 6.5 MEDIUM (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N
Weakness (CWE): CWE-444
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: GitHub_M
NVD analysis: Modified
Record last updated: Oct 8, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

netty netty netty:netty (from the name)	through 4.1.7.0.Final	CNA record
netty netty netty:netty	before 4.1.71	NVD
quarkus quarkus quarkus:quarkus	before 2.5.3	NVD
netapp oncommand_workflow_automation netapp:oncommand_workflow_automation	all versions	NVD
netapp snapcenter netapp:snapcenter	all versions	NVD
oracle banking_deposits_and_lines_of_credit_servicing oracle:banking_deposits_and_lines_of_credit_servicing	2.7	NVD
oracle banking_party_management oracle:banking_party_management	2.7.0	NVD
oracle banking_platform oracle:banking_platform	2.6.2	NVD
oracle coherence oracle:coherence	12.2.1.4.0; 14.1.1.0.0	NVD
oracle communications_cloud_native_core_binding_support_function oracle:communications_cloud_native_core_binding_support_function	1.11.0	NVD
1–10 of 19

References

References

https://github.com/netty/netty/security/advisories/GHSA-wx5j-54mm-rqqq
https://github.com/netty/netty/commit/07aa6b5938a8b6ed7a6586e066400e2643897323
https://www.oracle.com/security-alerts/cpuapr2022.html
https://security.netapp.com/advisory/ntap-20220107-0003/
https://www.oracle.com/security-alerts/cpujul2022.html
https://lists.debian.org/debian-lts-announce/2023/01/msg00008.html	mailing-list
https://www.debian.org/security/2023/dsa-5316	vendor-advisory

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.