What is CVE-2023-45727?

CVE-2023-45727 is a high-severity vulnerability in Northgrid Proself, classified under Improper Restriction of XML External Entity Reference (XXE). CVSS score: 7.5/10. Published 2023-10-18.

How severe is CVE-2023-45727?

High severity. CVSS v3 base score is 7.5 out of 10.

Is CVE-2023-45727 known to be exploited?

Yes. CVE-2023-45727 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2024-12-03), indicating it is being actively exploited. 3 public proof-of-concept repositories are indexed.

XXE in Northgrid Proself

CVE-2023-45727

Proself Enterprise/Standard Edition Ver5.62 and earlier, Proself Gateway Edition Ver1.65 and earlier, and Proself Mail Sanitize Edition Ver1.08 and earlier allow a remote unauthenticated attacker to conduct XML External Entity (XXE) attacks. By processing a specially crafted request containing malformed XML data, arbitrary files on the server containing account information may be read by the attacker.

Vulnerability class: XXE (XML External Entity)

Published 2023-10-18 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N.

EPSS exploit prediction

EPSS: 0.035 (89.1th percentile), scored 2026-10-19.

Low probability of exploitation in the next 30 days, but still tracked. 89th percentile — 89.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.035 · newest: 0.035 · change: 0.000

Affected products

Northgrid Proself
North Grid Corporation Proself Enterprise/standard Edition — versions Ver5.62 and earlier
North Grid Corporation Proself Gateway Edition — versions Ver1.65 and earlier
North Grid Corporation Proself Mail Sanitize Edition — versions Ver1.08 and earlier

Weakness classification (CWE)

CWE-611 — Improper Restriction of XML External Entity Reference (XXE)

CISA KEV (Known Exploited Vulnerabilities)

This CVE is on the CISA KEV catalog, added on 2024-12-03. CISA KEV inclusion means CISA has confirmed in-the-wild exploitation; US federal agencies are required to remediate within a published due date.

BOD 22-01 due date: 2024-12-24.

Required action: Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

Public proof-of-concept exploits

References

www.proself.jp/information/153/ (Vendor Advisory)
jvn.jp/en/jp/JVN95981460/ (Third Party Advisory)
134c704f-9b21-4f2e-91b3-4a467353bcc0 (US Government Resource)

Frequently asked questions

What is CVE-2023-45727?: CVE-2023-45727 is a high-severity vulnerability in Northgrid Proself, classified under Improper Restriction of XML External Entity Reference (XXE). CVSS score: 7.5/10. Published 2023-10-18.
How severe is CVE-2023-45727?: High severity. CVSS v3 base score is 7.5 out of 10.
Is CVE-2023-45727 known to be exploited?: Yes. CVE-2023-45727 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2024-12-03), indicating it is being actively exploited. 3 public proof-of-concept repositories are indexed.