MEDIUM
CVE-2020-15693
CWE-74Published: August 14, 2020· Updated: Jun 17, 2026
6.5
CVSS v3.1
Official Description
In Nim 1.2.4, the standard library httpClient is vulnerable to a CR-LF injection in the target URL. An injection is possible if the attacker controls any part of the URL provided in a call (such as httpClient.get or httpClient.post), the User-Agent header value, or custom HTTP header names or values.
Technical Analysis
CVE-2020-15693 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
ConfidentialityLow
IntegrityLow
AvailabilityNone
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
Affected Vendors & Products
nim-lang1 product(s)
nim
Source: NVD CPE · 1 total CPE entries
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 (8)
→
http://www.openwall.com/lists/oss-security/2021/02/04/2Exploit · Mailing List · Third Party Advisory
→
https://consensys.net/diligence/vulnerabilities/nim-httpclient-header-crlf-injection/Exploit · Third Party Advisory
→
https://github.com/nim-lang/Nim/blob/dc5a40f3f39c6ea672e6dc6aca7f8118a69dda99/lib/pure/httpclient.nim#L1023Patch · Third Party Advisory
→
https://nim-lang.org/blog/2020/07/30/versions-126-and-108-released.htmlRelease Notes · Third Party Advisory
→
http://www.openwall.com/lists/oss-security/2021/02/04/2Exploit · Mailing List · Third Party Advisory
→
https://consensys.net/diligence/vulnerabilities/nim-httpclient-header-crlf-injection/Exploit · Third Party Advisory
→
https://github.com/nim-lang/Nim/blob/dc5a40f3f39c6ea672e6dc6aca7f8118a69dda99/lib/pure/httpclient.nim#L1023Patch · Third Party Advisory
→
https://nim-lang.org/blog/2020/07/30/versions-126-and-108-released.htmlRelease Notes · Third Party Advisory
Quick Facts
CVE IDCVE-2020-15693
CVSS Score6.5 / 10
SeverityMEDIUM
WeaknessCWE-74
CISA KEVNo
Affected1 vendor(s)
PublishedAug 14, 2020
Related CVEs (CWE-74)
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2020-15693 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.COM. CVE data is provided under the NVD usage policy.