CVE-2026-19024: CWE-476 NULL pointer dereference in The HDF Group HDF5
A NULL pointer dereference vulnerability exists in the H5Pget_fill_value function of The HDF Group's HDF5 library before version 2.1.1. This flaw occurs when processing a dataset with a version 1 or 2 fill value message that has the "defined" flag set and a negative size field, which is not normalized properly. This leads to a NULL datatype pointer being passed to H5T_path_find, causing a denial of service.
AI Analysis
Technical Summary
CVE-2026-19024 describes a NULL pointer dereference in the H5Pget_fill_value function of HDF5 versions prior to 2.1.1. The vulnerability occurs when a dataset's fill value message of version 1 or 2 has the "defined" flag set along with a negative size field. This negative size is not properly normalized to the library's "undefined" sentinel value, resulting in a NULL datatype being passed to the H5T_path_find function. This causes a denial of service condition by crashing the application using the vulnerable HDF5 library.
Potential Impact
An attacker can cause a denial of service by triggering a NULL pointer dereference in the HDF5 library. This results in application or service crashes when processing specially crafted datasets with malformed fill value messages. There is no indication of code execution or data corruption beyond the denial of service.
Mitigation Recommendations
A fix is available in HDF5 version 2.1.1 that addresses this NULL pointer dereference vulnerability. Users should upgrade to version 2.1.1 or later to remediate this issue. No other mitigation steps are indicated.
CVE-2026-19024: CWE-476 NULL pointer dereference in The HDF Group HDF5
Description
A NULL pointer dereference vulnerability exists in the H5Pget_fill_value function of The HDF Group's HDF5 library before version 2.1.1. This flaw occurs when processing a dataset with a version 1 or 2 fill value message that has the "defined" flag set and a negative size field, which is not normalized properly. This leads to a NULL datatype pointer being passed to H5T_path_find, causing a denial of service.
CVSS v4.0
Score 8.2high
Affected software
Run on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-19024 describes a NULL pointer dereference in the H5Pget_fill_value function of HDF5 versions prior to 2.1.1. The vulnerability occurs when a dataset's fill value message of version 1 or 2 has the "defined" flag set along with a negative size field. This negative size is not properly normalized to the library's "undefined" sentinel value, resulting in a NULL datatype being passed to the H5T_path_find function. This causes a denial of service condition by crashing the application using the vulnerable HDF5 library.
Potential Impact
An attacker can cause a denial of service by triggering a NULL pointer dereference in the HDF5 library. This results in application or service crashes when processing specially crafted datasets with malformed fill value messages. There is no indication of code execution or data corruption beyond the denial of service.
Mitigation Recommendations
A fix is available in HDF5 version 2.1.1 that addresses this NULL pointer dereference vulnerability. Users should upgrade to version 2.1.1 or later to remediate this issue. No other mitigation steps are indicated.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- GHSA-c7cf-qx8c-5ph7
- Osv Schema Version
- 1.4.0
- Aliases
- ["CVE-2026-19024"]
- Ecosystems
- []
- Database Specific Severity
- HIGH
- Cvss Version
- 4.0
Threat ID: 6a74cfb1bf8831d5391b267b
Added to database: 08/06/2026, 18:17:21 UTC
Last enriched: 08/06/2026, 19:39:24 UTC
Last updated: 08/07/2026, 03:40:59 UTC
Views: 6
Community Reviews
0 reviewsCrowdsource mitigation strategies, share intel context, and vote on the most helpful responses. Sign in to add your voice and help keep defenders ahead.
Want to contribute mitigation steps or threat intel context? Sign in or create an account to join the community discussion.
Actions
Updates to AI analysis require Pro Console access. Upgrade inside Console → Billing.
Need more coverage?
Upgrade to Pro Console for AI refresh and higher limits.
For incident response and remediation, OffSeq services can help resolve threats faster.
Latest Threats
Check if your credentials are on the dark web
Instant breach scanning across billions of leaked records. Free tier available.