Cyber Resilience

CVE-2025-63909

Cohesity Tranzman 4.0

Public PoC
Published
03 March 2026
Modified
05 March 2026
CVSS Score v3.1 7.2
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0033 25th percentile
Risk Priority 52 floored blend · peak EPSS

CVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.

Summary

CVE-2025-63909 is a high-severity Improper Privilege Management (CWE-269) vulnerability in Cohesity Tranzman. Its CVSS base score is 7.2 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Abuse Elevation Control Mechanism (T1548); ranked at the 25th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified map to AC-2 (Account Management) and AC-24 (Access Control Decisions) — see the control section below for these in your framework.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

CVE-2025-63909 is an incorrect access control vulnerability affecting the /opt/SRLtzm/bin/TapeDumper component in Cohesity TranZman Migration Appliance Release 4.0 Build 14614. This flaw, linked to CWE-269 (Improper Privilege Management), enables privilege escalation to root privileges along with the ability to read and write arbitrary files on the affected system. The vulnerability carries a CVSS v3.1 base score of 7.2 (High), reflecting network accessibility, low attack complexity, and high impacts on confidentiality, integrity, and availability.

Exploitation requires high privileges (PR:H), allowing a privileged attacker with network access to the appliance to trigger the issue without user interaction. Successful exploitation grants root-level access, enabling full arbitrary file read and write operations, which could lead to complete system compromise, data exfiltration, or persistent backdoor installation.

Mitigation details and advisories are documented in the referenced sources, including a GitHub Gist at https://gist.github.com/GregDurys/d402038147e36de5908159d9722072ef and the Cohesity TranZman CVEs repository at https://github.com/GregDurys/Cohesity-TranZman-CVEs. Security practitioners should consult these for patch availability or workarounds specific to Release 4.0 Build 14614.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

Incorrect access control in the component /opt/SRLtzm/bin/TapeDumper of Cohesity TranZman Migration Appliance Release 4.0 Build 14614 allows attackers to escalate privileges to root and read and write arbitrary files.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1548 Abuse Elevation Control Mechanism Privilege Escalation
Adversaries may circumvent mechanisms designed to control privilege elevation to gain higher-level permissions.
T1134 Access Token Manipulation Stealth
Adversaries may modify access tokens to operate under a different user or system security context to perform actions and bypass access controls.
T1548.001 Setuid and Setgid Privilege Escalation
An adversary may abuse configurations where an application has the setuid or setgid bits set in order to get code running in a different (and possibly more privileged) user’s context.
T1548.003 Sudo and Sudo Caching Privilege Escalation
Adversaries may perform sudo caching and/or use the sudoers file to elevate privileges.
T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
T1078 Valid Accounts Stealth
Adversaries may obtain and abuse credentials of existing accounts as a means of gaining Initial Access, Persistence, Privilege Escalation, or Defense Evasion.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2025-63910Same product: Cohesity Tranzman
CVE-2025-63912Same product: Cohesity Tranzman
CVE-2025-63911Same product: Cohesity Tranzman
CVE-2025-67840Same product: Cohesity Tranzman
CVE-2025-39202Shared CWE-269
CVE-2024-33223Shared CWE-269
CVE-2023-21114Shared CWE-269
CVE-2023-47868Shared CWE-269
CVE-2024-27301Shared CWE-269
CVE-2024-0832Shared CWE-269

Affected Assets

cohesity
tranzman
4.0

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)
  • 3 hardening rules · 3 OS baselines
Validate
Prove the fix (OWASP ASVS)

Mitigating Controls (NIST 800-53 r5) AI

Account management directly governs assignment and tracking of privileges so proper implementation stops the weakness from being introduced.

Requiring explicit access-control decisions ensures privileges are evaluated rather than assumed or omitted.

Access enforcement applies the correct privilege checks at every request, structurally preventing unintended spheres of control.

Separation of duties constrains how privileges may be assigned, reducing the chance of overly broad actor control.

Least privilege is the direct countermeasure to improper privilege management; implementing it eliminates the root cause.

Binding security attributes to subjects/objects supplies the mechanism needed to track and enforce privileges correctly.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.AA-05 mostly match
prevents

PR.AA-05 enforces least privilege/SoD and periodic reviews that directly remove most privilege-assignment defects, yet CWE-269 also covers escalation paths and role design outside a single access-management control.

PR.AA-01 partial match
prevents

PR.AA-01 supplies credential/identity lifecycle support that can reduce some privilege-assignment errors but does not itself assign, modify, or check privileges, leaving most of CWE-269's risk unaddressed.

PR.PS-01 partial match
prevents

Config baselines and default reviews can enforce some privilege-related settings (one facet) but do not address code-level assignment/tracking logic that defines CWE-269.

PR.PS-05 partial match
prevents

PR.PS-05 can partially limit exploitability of some privilege issues via execution restrictions, but does not address the core design/implementation flaws of CWE-269 at all.

PR.DS-10 none match
prevents

PR.DS-10 protects data-in-use without touching privilege assignment/tracking, so it neither prevents CWE-269 nor removes more than one narrow facet of its risk.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

prevents

Requiring owner approval, segregation of duties, and periodic reviews prevents the assignment of excessive or unnecessary privileges to users or processes.

prevents

Enforcing minimum-necessary privileges, temporary grants, and separation of administrative versus normal identities prevents the over-assignment of rights that CWE-269 describes.

prevents

Dynamic techniques that grant the minimum necessary rights for a given time window and revoke them afterward reduce the window in which excessive or unnecessary privileges can be exploited.

prevents

Explicit restrictions on privileged access and segregation of duties limit the scope of privileges that can be assigned, reducing the chance that excessive or unnecessary privileges are granted to entities.

prevents

Defining and communicating authorization levels for each role limits the assignment of excessive or unnecessary privileges.

mitigates

Separating duties such as developing software from administering production systems prevents any one person from accumulating excessive privileges that would constitute improper privilege management.

Hardening callouts derived

Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (authoritative rows only; rows rated `none` are excluded).

Windows 10 (1 rule)
  • V-220712 Only accounts responsible for the administration of a system must have Administrator rights on the system. prevents CWE-269
Windows Server 2016 (1 rule)
  • V-225007 Only administrators responsible for the member server or standalone or nondomain-joined system must have Administrator rights on the system. prevents CWE-269
Windows Server 2019 (1 rule)
  • V-205746 Windows Server 2019 must only allow Administrators responsible for the member server or standalone or nondomain-joined system to have Administrator rights on the system. prevents CWE-269

References