CVE-2025-6858VulnerabilityPublished 29 Jun 2025Updated 30 Jun 2025

CVE-2025-6858: HDF5 · NULL Pointer Dereference

Affects HDF5Source CVE Database V5

Not known to be exploited · CVSS 4.8 Medium.

Data as of 26 Oct 2026, 06:26 UTC

CVSS 4.0 base score

4.8Medium

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 0.2% chance of exploitation in 30 days – higher than 15% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

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

Base metrics

Attack Vector: Local
Attack Complexity: Low
Attack Requirements: None
Privileges Required: Low
User Interaction: None
Vulnerable system confidentiality: None
Vulnerable system integrity: None
Vulnerable system availability: Low
Subsequent system confidentiality: None
Subsequent system integrity: None
Subsequent system availability: None

Threat metrics

Exploit Maturity: POC

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Local: The vulnerable system is not bound to the network stack and the attacker’s path is via read/write/execute capabilities. Either the attacker exploits the vulnerability by accessing the target system locally (e.g., keyboard, console), or through terminal emulation (e.g., SSH); or the attacker relies on User Interaction by another person to perform actions required to exploit the vulnerability (e.g., using social engineering techniques to trick a legitimate user into opening a malicious document).
Attack Complexity: Low: The attacker must take no measurable action to exploit the vulnerability. The attack requires no target-specific circumvention to exploit the vulnerability. An attacker can expect repeatable success against the vulnerable system.
Attack Requirements: None: The successful attack does not depend on the deployment and execution conditions of the vulnerable system. The attacker can expect to be able to reach the vulnerability and execute the exploit under all or most instances of the vulnerability.
Privileges Required: Low: The attacker requires privileges that provide basic capabilities that are typically limited to settings and resources owned by a single low-privileged user. Alternatively, an attacker with Low privileges has the ability to access only non-sensitive resources.
User Interaction: None: The vulnerable system can be exploited without interaction from any human user, other than the attacker.
Vulnerable system confidentiality: None: There is no loss of confidentiality within the Vulnerable System.
Vulnerable system integrity: None: There is no loss of integrity within the Vulnerable System.
Vulnerable system availability: Low: Performance is reduced or there are interruptions in resource availability. Even if repeated exploitation of the vulnerability is possible, the attacker does not have the ability to completely deny service to legitimate users. The resources in the Vulnerable System are either partially available all of the time, or fully available only some of the time, but overall there is no direct, serious consequence to the Vulnerable System.
Subsequent system confidentiality: None: There is no loss of confidentiality within the Subsequent System or all confidentiality impact is constrained to the Vulnerable System.
Subsequent system integrity: None: There is no loss of integrity within the Subsequent System or all integrity impact is constrained to the Vulnerable System.
Subsequent system availability: None: There is no impact to availability within the Subsequent System or all availability impact is constrained to the Vulnerable System.
Exploit Maturity: POC: Based on threat intelligence sources each of the following must apply: · Proof-of-concept is publicly available · No knowledge of reported attempts to exploit this vulnerability · No knowledge of publicly available solutions used to simplify attempts to exploit the vulnerability

Definitions: FIRST CVSS v4.0 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 29 Jun 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 2026-10-26.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Affected software

Product	Affected	Fixed in
GitHubhdfgroup/hdf5`pkg:github/hdfgroup/hdf5`Other threats	Affected =1.14.6	Fixed in–

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AI-suggested

To mitigate CVE-2025-6858, European organizations should: 1) Upgrade to a patched version of HDF5 once available, or apply vendor-provided patches promptly. 2) Implement strict access controls to limit local user privileges and restrict access to systems running vulnerable HDF5 versions, minimizing the risk of local exploitation. 3) Monitor systems for unusual crashes or application failures related to HDF5 usage, enabling early detection of exploitation attempts. 4) Employ application whitelisting and endpoint protection to prevent unauthorized code execution that could leverage this vulnerability. 5) In environments where upgrading is not immediately feasible, consider isolating or sandboxing applications using HDF5 to contain potential crashes and reduce impact on critical systems. 6) Conduct regular security training to raise awareness about local privilege escalation and lateral movement risks that could facilitate exploitation. 7) Review and harden system configurations to reduce the attack surface, including disabling unnecessary local accounts and services.

Description

A vulnerability was found in HDF5 1.14.6 and classified as problematic. Affected by this issue is the function H5C__flush_single_entry of the file src/H5Centry.c. The manipulation leads to null pointer dereference. The attack needs to be approached locally. The exploit has been disclosed to the public and may be used.

Impact

For European organizations, the impact of CVE-2025-6858 primarily involves potential denial of service conditions in applications that utilize HDF5 version 1.14.6. This could affect research institutions, universities, engineering firms, and industries such as aerospace, automotive, pharmaceuticals, and energy sectors that rely on HDF5 for large-scale data storage and analysis. Disruptions caused by application crashes could delay critical data processing tasks, impacting productivity and operational continuity. Since exploitation requires local access and low privileges, the threat is more relevant in environments where multiple users share systems or where attackers may gain initial foothold through other means. The vulnerability does not directly lead to data breaches or unauthorized data modification but could be leveraged as part of a broader attack chain to destabilize systems. Organizations with automated data pipelines or high-performance computing clusters using HDF5 may experience service interruptions. The absence of known exploits in the wild currently reduces immediate risk, but public disclosure of exploit details necessitates timely remediation to prevent future attacks.

References

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 29 Jun 2025, 11:24 UTC

Technical details

References

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