CVE-2025-6856
published 2025-06-29CVE-2025-6856: A vulnerability, which was classified as problematic, was found in HDF5 1.14.6. Affected is the function H5FL__reg_gc_list of the file src/H5FL.c. The…
PriorityP344high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.20%
10.4th percentile
A vulnerability, which was classified as problematic, was found in HDF5 1.14.6. Affected is the function H5FL__reg_gc_list of the file src/H5FL.c. The manipulation leads to use after free. Attacking locally is a requirement. The exploit has been disclosed to the public and may be used.
Affected
5 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | hdf5 | — | — |
| hdfgroup | hdf5 | — | — |
| msrc | azl3_hdf5_1.14.4.3-1_on_azure_linux_3.0 | — | — |
| msrc | azl3_mozjs_102.15.1-1_on_azure_linux_3.0 | — | — |
| msrc | cbl2_hdf5_1.14.4-1_on_cbl_mariner_2.0 | — | — |
CVSS provenance
nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
nvdv4.01.9LOWCVSS: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/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
nvdv2.01.7LOWAV:L/AC:L/Au:S/C:N/I:N/A:P
osv4.8MEDIUM
vendor_msrc8.8HIGH
vendor_debian4.8LOW
vendor_redhat4.8MEDIUM
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GHSA
GHSA-wxfp-rw9f-g4g7: A vulnerability, which was classified as problematic, was found in HDF5 1
ghsa_unreviewed·2025-06-29
CVE-2025-6856 [MEDIUM] CWE-119 GHSA-wxfp-rw9f-g4g7: A vulnerability, which was classified as problematic, was found in HDF5 1
A vulnerability, which was classified as problematic, was found in HDF5 1.14.6. Affected is the function H5FL__reg_gc_list of the file src/H5FL.c. The manipulation leads to use after free. Attacking locally is a requirement. The exploit has been disclosed to the public and may be used.
OSV
CVE-2025-6856: A vulnerability, which was classified as problematic, was found in HDF5 1
osv·2025-06-29·CVSS 4.8
CVE-2025-6856 [MEDIUM] CVE-2025-6856: A vulnerability, which was classified as problematic, was found in HDF5 1
A vulnerability, which was classified as problematic, was found in HDF5 1.14.6. Affected is the function H5FL__reg_gc_list of the file src/H5FL.c. The manipulation leads to use after free. Attacking locally is a requirement. The exploit has been disclosed to the public and may be used.
Red Hat
hdf5: HDF5 Use-After-Free Vulnerability
vendor_redhat·2025-06-29·CVSS 4.8
CVE-2025-6856 [MEDIUM] CWE-119 hdf5: HDF5 Use-After-Free Vulnerability
hdf5: HDF5 Use-After-Free Vulnerability
A vulnerability, which was classified as problematic, was found in HDF5 1.14.6. Affected is the function H5FL__reg_gc_list of the file src/H5FL.c. The manipulation leads to use after free. Attacking locally is a requirement. The exploit has been disclosed to the public and may be used.
A flaw was found in hdf5. The H5FL__reg_gc_list function in src/H5FL.c contains a use-after-free condition, requiring local attacker interaction. Manipulation of the file triggers this condition, potentially leading to a denial of service. This vulnerability stems from improper memory management during garbage collection list registration.
Mitigation: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product
Microsoft
HDF5 H5FL.c H5FL__reg_gc_list use after free
vendor_msrc·2025-06-10·CVSS 3.3
CVE-2025-6856 [MEDIUM] CWE-416 HDF5 H5FL.c H5FL__reg_gc_list use after free
HDF5 H5FL.c H5FL__reg_gc_list use after free
FAQ: Is Azure Linux the only Microsoft product that includes this open-source library and is therefore potentially affected by this vulnerability?
One of the main benefits to our customers who choose to use the Azure Linux distro is the commitment to keep it up to date with the most recent and most secure versions of the open source libraries with which the distro is composed. Microsoft is committed to transparency in this work which is why we began publishing CSAF/VEX in October 2025. See this blog post for more information. If impact to additional products is identified, we will update the CVE to reflect this.
Mariner: Mariner
VulDB: VulDB
Customer Action Required: Yes
Remediation: CBL-Mariner Releases
Reference: https://learn.microsoft.
Debian
CVE-2025-6856: hdf5 - A vulnerability, which was classified as problematic, was found in HDF5 1.14.6. ...
vendor_debian·2025·CVSS 4.8
CVE-2025-6856 [MEDIUM] CVE-2025-6856: hdf5 - A vulnerability, which was classified as problematic, was found in HDF5 1.14.6. ...
A vulnerability, which was classified as problematic, was found in HDF5 1.14.6. Affected is the function H5FL__reg_gc_list of the file src/H5FL.c. The manipulation leads to use after free. Attacking locally is a requirement. The exploit has been disclosed to the public and may be used.
Scope: local
bookworm: open
bullseye: open
forky: open
sid: open
trixie: open
Microsoft
The WebGL `DrawElementsInstanced` method was susceptible to a heap buffer overflow when used on systems with the Mesa VM driver. This issue could allow an attacker to perform remote code execution an
vendor_msrc·2023-12-12·CVSS 8.8
CVE-2023-6856 [HIGH] CWE-787 The WebGL `DrawElementsInstanced` method was susceptible to a heap buffer overflow when used on systems with the Mesa VM driver. This issue could allow an attacker to perform remote code execution an
The WebGL `DrawElementsInstanced` method was susceptible to a heap buffer overflow when used on systems with the Mesa VM driver. This issue could allow an attacker to perform remote code execution and sandbox escape. This vulnerability affects Firefox ESR Is Azure Linux the only Microsoft product that includes this open-source library and is therefore potentially affected by this vulnerability?
One of the main benefits to our customers who choose to use the Azure Linux distro is the commitment to keep it up to date with the most recent and most secure versions of the open source libraries with which the distro is composed. Microsoft is committed to transparency in this work which is why we began publishing CSAF/VEX in October 2025. See this blog post for more information. If impact to addi
No detection rules found.
No public exploits indexed.
Bugzilla
CVE-2026-6856 keycloak: keycloak: acceptable AAGUID policy bypass via packed self-attestation in WebAuthn registration
bugzilla·2026-04-21·CVSS 3.1
CVE-2026-6856 [LOW] CVE-2026-6856 keycloak: keycloak: acceptable AAGUID policy bypass via packed self-attestation in WebAuthn registration
CVE-2026-6856 keycloak: keycloak: acceptable AAGUID policy bypass via packed self-attestation in WebAuthn registration
WebAuthn AAGUID policy bypass via packed self-attestation. Similar to CVE-2025-12150. When direct attestation is requested but the authenticator sends self-attestation (no x5c), the AAGUID is unverified, allowing bypass of the acceptable AAGUID allowlist.
Affects RHBK 26.4 and Keycloak 26.6. Patch in progress.
Bugzilla
CVE-2025-6856 hdf5: HDF5 Use-After-Free Vulnerability [fedora-42]
bugzilla·2025-06-30·CVSS 1.9
CVE-2025-6856 [LOW] CVE-2025-6856 hdf5: HDF5 Use-After-Free Vulnerability [fedora-42]
CVE-2025-6856 hdf5: HDF5 Use-After-Free Vulnerability [fedora-42]
More information about this security flaw is available in the following bug:
https://bugzilla.redhat.com/show_bug.cgi?id=2375414
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.
Discussion:
This message is a reminder that Fedora Linux 42 is nearing its end of life.
Fedora will stop maintaining and issuing updates for Fedora Linux 42 on 2026-05-13.
It is Fedora's policy to close all bug reports from releases that are no longer
maintained. At that time this bug will be closed as EOL if it remains open with a
'version' of '42'.
Package Maintainer: If
2025-06-29
Published