Home/CVE/The parser in accepts requests with a space (SP) right after the header name before the colon. This can lead to HTTP Req
CVE

CVE-2021-22959

The parser in accepts requests with a space (SP) right after the header name before the colon. This can lead to HTTP Req

The parser in accepts requests with a space (SP) right after the header name before the colon. This can lead to HTTP Request Smuggling (HRS) in llhttp < v2.1.4 and < v6.0.6.

MEDIUM · CVSS 6.5 EPSS 0.00164
Schedule remediation
  • Public exploit or PoC is available
Sigma rules0 YARA rules0
⬡

Weakness Classification

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

Affected Products & Versions

4
llhttp< 2.1.4
llhttp>= 3.0.0 and < 6.0.6
oracle graalvmall versions
debian linuxall versions
⚠

Public Exploits & PoCs

1
pochackerone.com · 1238709hackerone.com
▣

Scoring & Timeline

6.5
MEDIUM · CVSS v3.1 · support@hackerone.com
View on NVD
Attack Vector
Network Adjacent Local Physical
Attack Complexity
Low High
Privileges Required
None Low High
User Interaction
None Required
Scope
Unchanged Changed
Confidentiality
None Low High
Integrity
None Low High
Availability
None Low High
Published to NVD15 Nov 2021 · 03:15 PM
CVSS VectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
⚑

Vendor Advisories

23
suse-csafopenSUSE-SU-2025:15095-1
suse-csafopenSUSE-SU-2024:11616-1
suse-csafopenSUSE-SU-2024:11637-1
suse-csafopenSUSE-SU-2024:12237-1
suse-csafSUSE-SU-2022:2855-1
🔗

References & Sources

2
Source URLs (vendor pages, mailing lists, write-ups). Exploit/PoC links are in their own section above to avoid duplication.
https://www.debian.org/security/2022/dsa-5170Mailing ListThird Party Advisory
https://www.oracle.com/security-alerts/cpujan2022.htmlPatchThird Party Advisory
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