Medium severity · published Nov 15, 2021
CVE-2021-22959
The parser in accepts requests with a space (SP) right after the header name before the colon
6.5
CVSS
3.2%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)3.2% · higher than 88% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
DL
Debian Linux · Debian
11.0 · source: NVD
GR
Graalvm · Oracle
20.3.4; 21.3.0 · source: NVD
LL
Llhttp · Llhttp
before 2.1.4; 3.0.0 before 6.0.6 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-22959
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-22959
Exploit
https://hackerone.com/reports/1238709
Mailing List
https://www.debian.org/security/2022/dsa-5170
Patch
https://www.oracle.com/security-alerts/cpujan2022.html
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