No exploitation reportedFix available

CVE-2021-41170

Q: Is CVE-2021-41170 actively exploited?

Active exploitation of CVE-2021-41170 has not been confirmed. Its EPSS score was 1.6% on 2026-10-22, the estimated probability of exploitation in the next 30 days.

Q: What is the CVSS score for CVE-2021-41170?

CVE-2021-41170 has a CVSS v3 base score of 9.8 (CRITICAL severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

No exploitation reported by the sources we read.

Published2021-11-08
Fixed in1.1.1
WeaknessCWE-277 · CWE-732 · CWE-74

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

Description

neoan3-apps/template is a neoan3 minimal template engine. Versions prior to 1.1.1 have allowed for passing in closures directly into the template engine. As a result values that are callable are executed by the template engine. The issue arises if a value has the same name as a method or function in scope and can therefore be executed either by mistake or maliciously. In theory all users of the package are affected as long as they either deal with direct user input or database values. A multi-step attack on is therefore plausible. Version 1.1.1 has addressed this vulnerability. Unfortunately only working with hardcoded values is safe in prior versions. As this likely defeats the purpose of a template engine, please upgrade.

Timeline

dates in UTC

2021-11-0819:15CVE publishedNVD

Observed activity

isMalicious corpus · updated 2026-10-23 18:48 UTC

Indicators tagged with this CVE, per day0 indicators over 7 days

Block these indicators

Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2021-41170?format=txt
CSV export: https://api.ismalicious.com/edl/cve/CVE-2021-41170?format=csv
TAXII collection of exploited CVEs
The EDL and CSV take an API key on the Pro plan.

Versions per branch

NVD

Neoan neoan3-template

Branch	Affected	Fixed in	Source
1.1	< 1.1.1	1.1.1	NVD

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Fix

Update Neoan neoan3-template to 1.1.1

Advisories and patches

Detection

Nuclei template: none so far
Exploit-DB: no entry
Proof-of-concept repositories: none listed

Sources

CNACVSS 3.19.8read 2026-10-23
NVDCVSS 3.19.8read 2026-10-23
NVDCVSS 2.07.5read 2026-10-23
CNAweakness (CWE)CWE-277, CWE-74read 2026-10-23
NVDweakness (CWE)CWE-732read 2026-10-23
FIRST EPSSEPSS score1.6 %2026-10-22

Technical details

CVSS v3 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Published: 2021-11-08
Last Modified: 2026-06-17
NVD status: Modified

Frequently asked questions

What is CVE-2021-41170?

Is CVE-2021-41170 actively exploited?

Active exploitation of CVE-2021-41170 has not been confirmed. Its EPSS score was 1.6% on 2026-10-22, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2021-41170?

CVE-2021-41170 has a CVSS v3 base score of 9.8 (CRITICAL severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

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