Public proof of conceptFix available

CVE-2021-25963

Q: Is CVE-2021-25963 actively exploited?

A proof-of-concept exploit exists for CVE-2021-25963, but active exploitation has not been confirmed at this time.

Q: What is the CVSS score for CVE-2021-25963?

CVE-2021-25963 has a CVSS v3 base score of 6.1 (MEDIUM severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.

A public proof of concept exists; no exploitation attested.

Published2021-09-30
WeaknessCWE-79

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

In Shuup, versions 1.6.0 through 2.10.8 are vulnerable to reflected Cross-Site Scripting (XSS) that allows execution of arbitrary javascript code on a victim browser. This vulnerability exists due to the error page contents not escaped.

Timeline

dates in UTC

2021-09-3008:15CVE publishedNVD

Observed activity

isMalicious corpus · updated 2026-10-23 21:37 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-2021-25963?format=txt
CSV export: https://api.ismalicious.com/edl/cve/CVE-2021-25963?format=csv
TAXII collection of exploited CVEs
The EDL and CSV take an API key on the Pro plan.

Versions per branch

NVD · OSV

Shuup

Branch	Affected	Fixed in	Source
2.10	≥ 1.6.0, ≤ 2.10.8	no fix published	NVD

shuup

Branch	Affected	Fixed in	Source
2.11	≥ 1.6.0, < 2.11.0	2.11.0	OSV

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

Fix

Advisories and patches

github.comPatch

Detection

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

Sources

CISA-ADPSSVC decisionpoc2025-04-30
OpenCVESSVC decisionpoc—
CNACVSS 3.16.1read 2026-10-23
NVDCVSS 3.16.1read 2026-10-23
NVDCVSS 2.04.3read 2026-10-23
CNAweakness (CWE)CWE-79read 2026-10-23
NVDweakness (CWE)CWE-79read 2026-10-23
FIRST EPSSEPSS score1.0 %2026-10-23
OSVaffected packages—

Technical details

CVSS v3 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Published: 2021-09-30
Last Modified: 2026-06-17
NVD status: Modified

Frequently asked questions

What is CVE-2021-25963?

Is CVE-2021-25963 actively exploited?

A proof-of-concept exploit exists for CVE-2021-25963, but active exploitation has not been confirmed at this time.

What is the CVSS score for CVE-2021-25963?

CVE-2021-25963 has a CVSS v3 base score of 6.1 (MEDIUM severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.

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Surveillance reads the versions in your stack — a domain, a lockfile or a list — checks each CVE against the ranges its sources publish, and alerts you when one you run is exploited or enters CISA KEV. A version it cannot read stays « version not verified ».

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