TI-2020-12365 Aliases CVE-2020-15693

In Nim 1.2.4, the standard library httpClient is vulnerable to a CR-LF injection in the…

LOW 33CWE-74Published 2020-08-14 · Updated 2024-08-04

Key facts

Attack vector: Network
Privileges required: None
User interaction: None
Attack complexity: Low
Impact type: —
Confidentiality · integrity · availability: Low · Low · None
Fix status: No fix listed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA.

Summary

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.

Why it matters now

EPSS 0.02131 82nd percentileScored 2026-11-07

Public exploit Yes 2 exploit referencesTagged by NVD

Fix No fix listed No fixed version in the sources yet

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
—	—	all versions	—	No fix listed	CNA

— Vendor— Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPE	Versions	Role	Vendor
cpe:2.3:a:nim-lang:nim::::::::	up to 1.2.6	Vulnerable	nim-lang

cpe:2.3:a:nim-lang:nim:*:*:*:*:*:*:*:* Versions up to 1.2.6 Vulnerable ·nim-lang

Remediation

No fixed version listed by the sources yet.

Vendor assessments

Red Hat

Red Hat's page for this CVE →

Not affected: 1 product

Red Hat

Timeline

2026-10-02 Threatist record created from CVE-2020-15693

References

Exploit 2

Patch 1

https://github.com/nim-lang/Nim/blob/dc5a40f3f39c6ea672e6dc6aca7f8118a69dda99/lib/pure/httpclient.nim#L1023

Advisory 1

https://nim-lang.org/blog/2020/07/30/versions-126-and-108-released.html

TI-2020-12364 In Nim 1.2.4, the standard library browsers mishandles the URL argument to… CVSS 3.1CRITICAL 9.8
TI-2020-12363 In Nim before 1.2.6, the standard library asyncftpclient lacks a check for whether a… CVSS 3.1CRITICAL 9.8
TI-2021-04471 Nimble arbitrary code execution for specially crafted package metadata CVSS 3.1HIGH 8.8
TI-2021-04473 Nimble fails to validate certificates due to insecure httpClient defaults CVSS 3.1HIGH 8.1
TI-2020-12366 In Nim 1.2.4, the standard library httpClient fails to properly validate the server… CVSS 3.1HIGH 7.5
TI-2021-04472 Nimble falls back to insecure http url when fetching packages CVSS 3.1HIGH 7.5

See all 8 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences