Vulnerability report

Exploitation Attempts Observed Confirmed Confidence Not in CISA KEV

CVE-2026-125883

Multiple XXE Vulnerabilities

N-able / N-central · affected before 26.4.1

Watch CVE-2026-125883 Browse KEV feed
Severity
CVSS 9.3 · Critical
Confidence
Confirmed
Exploit status
Exploitation Attempts Observed in the Wild
EPSS
—
First observed
09 Nov 2026
Last observed
11 Nov 2026

Decision summary

What security teams need to know first

Direct answers before the deeper technical record.

What it is

CVE-2026-125883 is an unauthenticated Multiple XXE Vulnerabilities affecting N-able N-central. Improper restriction of XML external entity reference vulnerability in N-able N-central allows XML Schema Poisoning.

Have exploitation attempts been observed?

Yes. Previdian sensors have observed 131 exploitation attempts, 3 unique attacker IPs, and 3 countries targeting CVE-2026-125883. First observed Nov 09, 2026; last observed Nov 11, 2026. Confidence is confirmed.

Who is affected?

N-able / N-central affected before 26.4.1.

What should we do?

Patch immediately, validate internet-facing exposure, and monitor for matching requests.

Overview

Improper restriction of XML external entity reference vulnerability in N-able N-central allows XML Schema Poisoning

Improper restriction of XML external entity reference vulnerability in N-able N-central allows XML Schema Poisoning.

This issue affects N-central: before 26.4.1.

N-able Affected
N-central
Before 26.4.1
View vendor advisory (opens in new tab)
Published
10 Nov 2026
Exploitation Attempts Reported
09 Nov 2026
Attack vector
Remote
Complexity
Low
Privileges
None
User interaction
None

CVE References

Exploitation evidence

Evidence of exploitation attempts

Third-party attestation and first-party sensor observation are shown separately so teams can judge the evidence chain.

Exploitation Attempts Observed in the Wild

Previdian

Recorded 09 Nov 2026

Previdian sensors observed exploitation attempts targeting this vulnerability.

Exploitation Attempts Observed

Previdian sensor

First observed 09 Nov 2026

Previdian sensors observed exploitation attempts targeting this vulnerability.

Proof of concept available

CVE

Recorded 09 Nov 2026

Public scanner or PoC coverage increases practical exploitability.

Known exploited vulnerability sources

Per-source evidence links for KEV attestations are available through the Previdian Pro API.

Learn about Pro API access
Source Added
Previdian Sensors First 2026-11-10 10:56 UTC

Operational indicators for this CVE are listed under Detection.

Sensor telemetry

Previdian Sensor Observations

Previdian sensor observations are exploitation attempts targeting this vulnerability. They do not show that the target was vulnerable or that the attempt succeeded. The cards and chart show volume, unique attackers, and daily activity.

131

Attempts observed

3

Unique attacker IPs

3

Attacker countries

DE · PL · US

1

Sensors observed

CVE-2026-125883 exploitation attempts over the last 7 days

Daily events observed by Previdian sensors

Updated 12 Nov 2026

0
0
0
81
2
48
0
6 Nov 7 Nov 8 Nov 9 Nov 10 Nov 11 Nov 12 Nov

First observed 09 Nov 2026 · Last observed 11 Nov 2026

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Detection

Operational artifacts and observed signals

Make the evidence actionable in scanner, SOC, and edge-control workflows.

Observed signals

Request targets
User-Agents
Callback hosts
15
5
1

Request targets and User-Agents available in Pro. Callback host details available in Enterprise.

Scanner coverage

No scanner integrations recorded yet.

Virtual patch status

No Previdian virtual patch is currently available. Future rules ship for ModSecurity, Cloudflare, and AWS WAF.

Learn about virtual patches →

Attacker IP Indicators

Attacker IP indicators observed · available in Pro and Enterprise.

Sensor-derived attacker IP indicators are available to Pro and Enterprise accounts under Detection and through the Pro API.

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Risk and context

Severity, weaknesses, and research context

CVSS v4.0

9.3 Critical

Potential damage if exploited. Separate from whether attackers are using it.

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:L/SC:N/SI:N/SA:N

EPSS

—

Estimated chance of exploitation in the next 30 days. Previdian's warning comes from evidence, not this score.

Weaknesses

Improper Restriction of XML External Entity Reference CWE-611

Recent mention · Tenable Blog

Able2Shell: Frequently asked questions for reported N-able N-central zero-day vulnerabilities

N-able released a hotfix for N-central that fixes seven CVEs after a researcher published proof-of-concept code for 33 alleged zero-day vulnerabilities. The researcher says one attack chain needs no credentials.Key TakeawaysAble2Shell is a set of 33 alleged vulnerabilities in...

Read full advisory

All Mentions

Recent mention · Tenable Blog

Able2Shell: Frequently asked questions for reported N-able N-central zero-day vulnerabilities

Tenable Blog · 11 Nov 2026

N-able released a hotfix for N-central that fixes seven CVEs after a researcher published proof-of-concept code for 33 alleged zero-day vulnerabilities. The researcher says one attack chain needs no credentials.Key TakeawaysAble2Shell is a set of 33 alleged vulnerabilities in N-able N-central, published with proof-of-concept code. The researcher says one chain lets an unauthenticated attacker run commands on the server.Security firms report exploitation attempts against N-central honeypots, but as of November 10, no confirmed compromise of a customer server has been reported.N-able released...

Recent mention · N-able Release Notes

N-central 2026.4 HF2 Release Notes

N-able Release Notes · 10 Nov 2026

Build Number: 2026.4.1.26 Last Updated: November 10th, 2026  N-central 2026.4 Hotfix 2 – Security Update N-central 2026.4 Hotfix 2 is a critical security update. It includes a number of security patches and technology updates that improve the overall security of N-central. This hotfix … Continue reading →

Recent mention · Rapid7

Critical vulnerabilities in N-able N-central prompt hosted shutdown

Rapid7 · 10 Nov 2026

OverviewOn November 9, 2026, N-able announced that it was responding to the public disclosure of critical vulnerabilities affecting N-central, its remote monitoring and management (RMM) platform.In a public disclosure titled Able2Shell, an independent researcher has published details and proof-of-concept (PoC) code covering 33 issues. According to the disclosure, the issues include unauthenticated remote code execution (RCE), privilege escalation to root, credential disclosure, and unauthorized account creation. One unauthenticated chain combines XML external entity (XXE) and...

Recent mention · The Hacker News

N-able Takes N-central Cloud Offline After Researcher Discloses 33 Zero-Days with PoC Exploits

The Hacker News · 10 Nov 2026

Ravie LakshmananNov 10, 2026Vulnerability / Enterprise Security N-able said it has taken N-central Hosted Environments offline and is urging on-premises customers to shut down their servers until further notice following the public disclosure of over 30 vulnerabilities collectively tracked as Able2Shell. "As a precautionary measure, we are temporarily taking our Hosted N-central environment offline while we take the necessary actions to secure the environment and implement appropriate remediation," N-able said. "During this time, customers will be unable to access their Hosted N-central...

Recent mention · N-able Uptime

N-able® N-central

N-able Uptime · 09 Nov 2026

**N-able® N-central** **N-central Critical Security Incident - Release Available** **IMPORTANT: N-central Critical Security Incident** N-able is currently responding to the public disclosure of critical vulnerabilities in N-central by an independent security researcher. We are now observing scanning activity associated with the published proof-of-concept code. **We continue to recommend that N-central servers remain offline until your server has been successfully upgraded.** **We have released N-central 2026.4 HF2, which addresses the critical security updates** and includes a number of...

Potential Proof of Concepts

These PoCs are unverified and could contain malware. Use at your own risk.

anonymous_xxe_nable_rce.py

public · Created 2026-11-09 18:35:00 UTC

CVE Record exploit — github.com

cve · Created Unknown

Timeline

From disclosure to observed exploitation attempts

  1. 08:59 UTC

    CVE ID assigned

    Previously tracked as VULN-2026-0007

  2. 21:19 UTC

    CVE published

    Vulnerability disclosed publicly

  3. 12:55 UTC

    CVE ID reserved

    Identifier reserved by the CNA

  4. 21:58 UTC

    Indicators of compromise added (3)

    Indicators of compromise recorded

  5. 21:58 UTC

    Observed by Previdian sensors

    Previdian sensors observed exploitation attempts targeting this vulnerability.

  6. 18:35 UTC

    Public PoC available

    Public proof-of-concept code published

  7. 17:35 UTC

    Added to the Previdian watchlist

    Pro and Enterprise Watch users had 1 day of early warning before Previdian KEV.

Pro API

Automate this intelligence

Confidence, exploit status, sensor telemetry, PoCs, scanner integrations, mentions, and tags are available programmatically for VM, SOC, and CTI workflows.

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  • Evidence confidence and provenance
  • First-party sensor telemetry
  • PoC and scanner references
  • Affected versions and enrichment
  • Automation-ready JSON delivery

GET /api/v2/pro/kevs/CVE-2026-125883

Sample API response 
{
  "cve_id": "CVE-2026-125883",
  "confidence": "Confirmed",
  "cvss_score": 9.3,
  "cvss_estimated": false,
  "epss_score": null,
  "exploit_status": {
    "exploited_in_the_wild": true,
    "active_exploitation_observed": true
  },
  "sensor_telemetry": { "attempts": 131, "sensors": 1 }
}