Security readout for executives and security teams
Plain-English summary
This flaw could let an unauthenticated attacker take over a vulnerable Hyland OnBase Timer Service remotely. The reported impact is full code execution as NT AUTHORITY\SYSTEM, making it business-critical where OnBase handles documents, workflows, or regulated records.
Executive priority
Treat as urgent for any exposed or business-critical OnBase environment. Prioritize discovery, vendor-guided remediation, and network restriction because the reported outcome is unauthenticated SYSTEM-level remote code execution.
Technical view
CVE-2025-34153 is insecure deserialization in Hyland OnBase .NET Remoting TCP channel. The TimerServer endpoint on TCP 6031, implemented in Hyland.Core.Timers.dll, deserializes untrusted BinaryFormatter input. Sources describe unauthenticated remote code execution on versions before 17.0.2.87; other versions may be affected.
Likely exposure
Exposure is most likely on OnBase deployments running the Timer Service with TCP 6031 reachable. Internet exposure is not required for serious risk; internal attacker access may be enough. Version scope beyond pre-17.0.2.87 is not fully clear from the provided evidence.
Exploitation context
The bundle marks KEV as false, so active exploitation is not established here. Public technical and exploit-labeled material is referenced, which raises validation urgency, but this assessment does not infer active attacks without cited evidence.
Researcher notes
Evidence supports CWE-502 insecure deserialization over .NET Remoting using BinaryFormatter on the TimerServer endpoint. The exact supported-version matrix and mitigation details should be confirmed in Hyland's advisory because the bundle notes other versions may be affected.
Mitigation direction
- Apply Hyland's security update or upgrade to a fixed supported OnBase version.
- Use Hyland bulletin OB2025-02 for mitigation and permission requirements.
- Restrict Timer Service network access to trusted systems where vendor guidance allows.
- Review OnBase service accounts and reduce unnecessary privileges where operationally supported.
- Monitor for unexpected Timer Service behavior until remediation is confirmed.
Validation and detection
- Inventory OnBase versions and identify hosts running the Timer Service.
- Confirm whether TCP 6031 is reachable from untrusted networks or broad internal segments.
- Verify affected hosts are at or beyond version 17.0.2.87 where applicable.
- Check Hyland advisory guidance for version-specific applicability and permissions.
- Review security logs for suspicious Timer Service activity around vulnerable hosts.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-502: Code execution behavior lookup
Code execution and unsafe deserialization weaknesses often justify reviewing execution behavior and process telemetry. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupExecution behavior lookup
The CVE wording references code or command execution, so execution technique review may help defensive triage. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2025-34153 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Critical
- CVSS
- 10 (4.0)
- Known Exploited
- No
- Published
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
SSVC decision data
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H——VulnCheckVulnerability scoring details
Base CVSS 4.0 score
10CriticalVector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H
Vulnerability timeline
Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.
- CVE reservedCVE Program
The CVE ID was reserved by the assigning CNA.
- CVE publishedCVE Program
The CVE record was published.
- CVE updatedCVE Program
The CVE record metadata indicates this as the latest update time.
ADP provider summaries
Source materials
- CVE List V5 sourceCVE List V5
- https://gist.github.com/VAMorales/32794cccc2195a935623a12ef32760dcCVE reference, VulnCheck · technical-description, exploit
- https://www.hyland.com/en/internal/onbase-unity-clientCVE reference, VulnCheck · product
- https://support.hyland.com/r/OnBase/WorkView/Foundation-24.1/WorkView/Installation/Upgrade-Considerations/Upgrading-to-OnBase-Version-Foundation-24.1CVE reference, VulnCheck · patch
- https://www.vulncheck.com/advisories/hyland-onbase-net-remoting-tcp-channel-unauthenticated-rceCVE reference, VulnCheck · third-party-advisory
- https://community.hyland.com/resources/bulletins-and-notices/210540-security-update-hyland-timer-service-bulletin-ob2025-02CVE reference, VulnCheck · vendor-advisory, mitigation
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Deserialization of Untrusted Data
Deserialization of Untrusted Data represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.