NVD / CVE Program· CNA synology

CVE-2023-52947: Missing authentication for critical function vulnerability in logout functionality in Synology Active Backup for Business Agent before 2.6.3

Noroxi assessment

Priority: Monitor (action score 13/100)

The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
Probability of exploitation in the next 30 days: 0.16% (FIRST EPSS).
Someone with local access to the system can trigger it. A low-privileged account is enough. No user action is required. No special conditions are required; it is repeatable.
Fixed version: Synology Synology Active Backup for Business Agent 2.7.0-3221.
Mentioned 1 time in Turkish national cyber security advisories (siberguvenlik.gov.tr).

Low priority for now. Upgrade to Synology Synology Active Backup for Business Agent 2.7.0-3221 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

Missing authentication for critical function vulnerability in logout functionality in Synology Active Backup for Business Agent before 2.6.3-3101 allows local users to logout the client via unspecified vectors. The backup functionality will continue to operate and will not be affected by the logout.

LowCVSS 3.3 · v3.1—No exploit Fix available

Published: Sep 26, 2024
Updated: Jun 17, 2026
EPSS: 0.1% · 5th percentile
CWE: CWE-306

Report tools

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Action score

Monitor

Low priority for now.

CVSS: 13 / 40 · 3.3 / 10
CISA KEV: 0 / 30 · Not listed
EPSS: 0 / 30 · 0.1%

CISA SSVC decision

Exploitation: none
Automatable: no
Technical impact: partial

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD: 3.3
CNA · synology: 4.0; 0.7 point gap

CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

Get told when this record changes

Not in KEV: no record of exploitation in the wild
No public exploit code on record
A fix has been released

If any of these changes, we'll tell you in the daily email digest.

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

Vendor	Product	CPE
synology	active backup for business agent	cpe:2.3:a:synology:active_backup_for_business_agent

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

synology active backup for business agentbefore 2.6.0-3101

Versions reported by the vendor

Affected version ranges reported by the assigning authority (synology). Independent of NVD's CPE analysis and usually ahead of it.

Synology Synology Active Backup for Business Agent
- before 2.7.0-3221affected · semver

Same product

synology: all records

Other highest-scoring records for the same primary product.

CVE-2024-47265Improper limitation of a pathname to a restricted directory ('Path Traversal') vulnerability in encrypted share umount functionality in Syno
26Monitor
CVE-2024-47264Improper limitation of a pathname to a restricted directory ('Path Traversal') vulnerability in agent-related functionality in Synology Acti
26Monitor
CVE-2025-66592An origin validation error vulnerability in Synology Active Backup for Business Agent before 3.1.0-4967 allows local users to write arbitrar
22Monitor

Published before and after this one in the same product

Later →CVE-2023-52948Sep 26, 2024 · Missing encryption of sensitive data vulnerability in settings functionality in Synology Active Backup for Business Agent before 2.7.0-3221
20Monitor
Later →CVE-2023-52949Sep 26, 2024 · Missing authentication for critical function vulnerability in proxy settings functionality in Synology Active Backup for Business Agent befo
22Monitor
Later →CVE-2023-52950Sep 26, 2024 · Missing encryption of sensitive data vulnerability in login component in Synology Active Backup for Business Agent before 2.7.0-3221 allows
21Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / package	Fixed version	Source
Synology Synology Active Backup for Business Agent	2.7.0-3221	Vendor (CNA)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

No history yet (it accumulates with the daily EPSS job).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

Zhao Runzi (赵润梓)finder

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

CVE-2023-529490 days apartMissing authentication for critical function vulnerability in proxy settings functionality in Synology Active Backup for Business Agent befo
22Monitor

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

CVE-2024-47264140 days apartImproper limitation of a pathname to a restricted directory ('Path Traversal') vulnerability in agent-related functionality in Synology Acti
26Monitor
CVE-2024-47265140 days apartImproper limitation of a pathname to a restricted directory ('Path Traversal') vulnerability in encrypted share umount functionality in Syno
26Monitor
CVE-2024-47266140 days apartImproper limitation of a pathname to a restricted directory ('Path Traversal') vulnerability in share file list functionality in Synology Ac
10Monitor

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

National notice (Türkiye Cybersecurity Directorate / USOM)

Official security notices citing this record; remediation advice is on the agency's page.

TR-24-1539 · Sep 26, 2024(Synology Çoklu Ürün Güvenlik Bildirimi)

All national notices →

Technical details

Attack conditions

Someone with local access to the system can trigger it.
A low-privileged account is enough.
No user action is required.
No special conditions are required; it is repeatable.

If successful

Confidentiality: none
Integrity: none
Availability: low · the service can be disrupted

Attack vector: Local
Attack complexity: Low
Privileges required: Low
User interaction: None
Scope: Unchanged
Confidentiality impact: None
Integrity impact: None
Availability impact: Low

Weakness class (CWE)

CWE-306 · Missing Authentication for Critical Function

CVSS vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L

nvd-primary

Root cause

A function added for development or support ships to production without authentication. It often relies on the assumption that it is “only reachable from the internal network.”

The bug in code

The whole CWE-306 class

A representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.

Vulnerable

1// Added for the support team
2app.post("/maintenance/reset", resetDevice);

Fixed

1if (config.maintenanceEnabled) {
2  app.post(
3    "/maintenance/reset",
4    requireSession, requireRole("admin"), resetDevice
5  );
6}

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

Attack patterns (CAPEC)

ATT&CK techniques

—

Change log

Fix✗ → ✓Sep 28, 2026, 10:09 PM UTC

For records you follow, these changes also arrive as notifications. →

References

www.synology.com/en-global/security/advisory/Synology_SA_24_11

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

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