CVE-2023-45727North Grid Proself Improper Restriction of XML External Entity (XXE) Reference Vulnerability
CVE-2023-45727 is a XML external entity in North Grid Proself, rated high (7.5 on CVSS 3.1).
Why this priority: Exploited in the wild: listed in CISA's KEV catalog.
Published · Updated · NVD status: Analyzed
What it is
The XML parser resolves external entities, so a crafted document can read local files or reach internal hosts.
How it is reached
An attacker can exploit it over the network, without an account, and nobody has to click anything.
What an attacker gains
A successful attack can read the data it protects. In practice, this kind of flaw lets an attacker read local files or reach internal hosts through the parser.
Is it being exploited?
CISA added it to the Known Exploited Vulnerabilities catalog on 2024-12-03: it is being exploited in the wild. It can be exploited automatically, at scale. EPSS estimates a 4.8% chance of exploitation activity in the next 30 days, higher than 92% of scored CVEs.
What to do
- Treat it as urgent: it is on CISA's KEV list. CISA's deadline for US federal agencies: 2024-12-24.
- Upgrade North Grid Proself to 5.63 or later.
- Until it is patched, keep it off the internet or behind a VPN, allowlist or authenticating proxy.
- Check exposed instances for signs of compromise, not only for the version.
Description from NVD
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.
What this means for your architecture.
A CVE names a product. Whether it matters depends on where that product sits in your systems: what reaches it, which trust boundary it guards and what it can reach once compromised. Veriom maps your components, their relationships and your trust boundaries from your code, cloud and delivery evidence, so you can see where a component like this sits. The radar itself does not look at your systems.
Components it touches
- Network edge devices: VPNs, firewalls, routers and gateways. They sit between the internet and internal networks, so a flaw in one is often the first step into everything behind it.
- XML and document parsers in APIs and import features. The flaw sits between uploaded or posted documents and the service parsing them.
Trust boundaries in play
- Internet-facing entry points. No account is needed. Any instance reachable from outside your perimeter, through a load balancer, gateway, VPN or exposed admin port, is in scope.
- Between uploaded or posted documents and the service parsing them. An attacker who crosses it can read local files or reach internal hosts through the parser.
Questions to answer about your own systems
- Where does North Grid Proself run in your systems, and at which version?
- Which of those instances can be reached from the internet or partner networks?
- What can it reach once compromised: which data stores, secrets and services?
Sources
- CVE records and CVSS scores from the NVD CVE API. This product uses the NVD API but is not endorsed or certified by the NVD.
- Exploitation status from CISA’s Known Exploited Vulnerabilities catalog.
- Exploit likelihood from FIRST’s Exploit Prediction Scoring System (EPSS), refreshed daily.
- Explanations are written by Veriom from fixed templates over each record’s data, not by a person reviewing each CVE. Descriptions are quoted from the records as published.