MEDIUM
CVE-2021-39241
NVD-CWE-noinfoPublished: August 17, 2021· Updated: Jun 17, 2026
5.3
CVSS v3.1
Official Description
An issue was discovered in HAProxy 2.0 before 2.0.24, 2.2 before 2.2.16, 2.3 before 2.3.13, and 2.4 before 2.4.3. An HTTP method name may contain a space followed by the name of a protected resource. It is possible that a server would interpret this as a request for that protected resource, such as in the "GET /admin? HTTP/1.1 /static/images HTTP/1.1" example.
Technical Analysis
CVE-2021-39241 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.
The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.
CVSS v3.1 Vector Breakdown
Exploitability
Attack VectorNetwork
Attack ComplexityLow
Privileges Req.None
User InteractionNone
ScopeUnchanged
Impact
ConfidentialityNone
IntegrityLow
AvailabilityNone
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
Affected Vendors & Products
Exploit & PoC Resources
NO KNOWN EXPLOITNo public exploit confirmed at this time
Exploit-DB
Offensive Security exploit database
GitHub PoC Search
Community PoC repositories
Rapid7 / Metasploit
Metasploit module search
PacketStorm
Security advisories & exploits
NVD Detail
Official NIST entry
MITRE CVE
CVE Program entry
External links open in a new tab. Always verify in a controlled environment before use.
Official Patches & Advisories
All References (10)
→
https://www.debian.org/security/2021/dsa-4960Third Party Advisory
→
https://www.debian.org/security/2021/dsa-4960Third Party Advisory
Quick Facts
CVE IDCVE-2021-39241
CVSS Score5.3 / 10
SeverityMEDIUM
WeaknessNVD-CWE-noinfo
CISA KEVNo
Affected3 vendor(s)
PublishedAug 17, 2021
Related CVEs (NVD-CWE-noinfo)
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2021-39241 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts
Data sourced from NVD (NIST), CISA KEV, and EPSS (FIRST). Analysis generated by CTIWatch. CVE data is provided under the NVD usage policy.