CVE-2020-23171

Exp

A vulnerability in all versions of Nim-lang allows unauthenticated attackers to write files to arbitrary directories via a crafted zip file with dot-slash characters included in the name of the crafted file.

Published: 2021-08-10 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2020-23171 is rated Exploit Available (53.3/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.66%). 1 public exploit reference(s) are indexed (Exploit-DB). Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2020-23171

EDB-ID Source Kind Published Link
— nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2020-23171

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.59% 0.66% +0.07%
2 2026-01-22 0.54% 0.59% +0.05%
3 2025-06-21 — 0.54% —

Full EPSS history (9 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2020-23171

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.5 3.1 MEDIUM
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N)
Service keeps running; no real outage angle.
 1.8 3.6 [email protected]
4.3 2.0 MEDIUM
AV:N/AC:M/Au:N/C:N/I:P/A:N Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:N)
No confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:N)
No availability impact.
 8.6 2.9 [email protected]

Weakness enumeration for CVE-2020-23171

OS Trackers for CVE-2020-23171

vendor priority summary link
ubuntu medium CVE-2020-23171 medium priority: Ubuntu including 1 source packages (nim), 13 status rows across 13 suites (bionic, focal, hirsute, impish, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): ignored 6, needs-triage 6, DNE 1. https://ubuntu.com/security/CVE-2020-23171

Affected software / configurations for CVE-2020-23171

Vendor Product Version Raw CPE
nim-lang nim-lang — cpe:2.3:a:nim-lang:nim-lang:*:*:*:*:*:*:*:*

References for CVE-2020-23171

URL Tags
https://github.com/nim-lang/zip/issues/54 Exploit Issue Tracking Third Party Advisory
cvelogic Threat Intelligence