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CVE-2026-19027Proof of concept (PoC) published · CISA

HDF5 out-of-bounds heap read in N-Bit filter decompression

CVSS score

6.9

EPSS probability

%0.2

Risk score

0.0

Published

2 mo ago

Patch status has not yet been verified

Resmî kaynaklarda yeterli kanıt bulunamadı. Bu sonuç “yama yok” anlamına gelmez.

Impact on My Inventory

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Vulnerability description

DayBreach CVE AI Research

CVE-2026-19027 has vendor, distribution, patch and security-source records on file. We can compare them and prepare an explanation linked to the evidence.

The H5Z__nbit_decompress_one_byte, H5Z__nbit_decompress_one_nooptype, and H5Z__nbit_decompress_one_atomic functions in H5Znbit.c in HDF5 prior to 2.3.0 advance a read index into the compressed chunk buffer without bounding it against the buffer's actual size. This allows attackers to cause an out-of-bounds heap read, and in constrained cases disclosure of adjacent heap memory into decompressed dataset values, via a crafted HDF5 file whose N-Bit filter parameters describe more decompressed data than the stored compressed chunk actually contains, triggered via H5Dread, e.g. by the h5ls or h5repack tools.

IMPACT: Affected Products and Software

Affected Products

The following products are affected by CVE-2026-19027 vulnerability. Where our threat engine knows the exact affected versions, they are listed below.

IDVENDORPRODUCTACTION
1The HDF GroupHDF5 View
2debianhdf5 (sid) View
3debianhdf5 (forky) View
4debianhdf5 (trixie) View
5debianhdf5 (bookworm) View
6debianhdf5 (bullseye) View
Total affected vendors: 2|Products: 6

RED HAT CSAF/VEX: Product Impact Check

Red Hat has not yet published a CSAF/VEX impact record for this CVE. This does not mean “not affected”.

SCORING: CVSS from Multiple Sources

CVSS Scores

The Common Vulnerability Scoring System is a standardised framework for assessing the severity of vulnerabilities in software and systems. We collect and display CVSS scores from several sources for each CVE.

SCOREVERSIONSEVERITYVECTORSOURCE
6.9CVSS V4_0MEDIUMCVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:L/VI:N/VA:H/SC:N/SI:N/SA:NCVE CNA
6.9CVSS V40MEDIUMCVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/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:XNVD

Patch and Remediation Guide

Solution & Remediation Advisory

Patch status unknown

İncelenen resmî kaynaklarda yama durumu doğrulanamadı. Bu sonuç “yama yok” anlamına gelmez.

Confirm the affected product and version against the source evidence above.
Restrict access to internet-facing services and apply network segmentation.
Until a patch is confirmed, follow the vendor advisory; do not read an unknown status as “no patch”.
Monitor server logs and network endpoints for signs of anomalous execution.

Public exploit and active exploitation status

Verified exploit intelligence

No verified public PoC, exploit repository or Metasploit module has been found for this CVE yet.

Weakness Classification and Attack Patterns (CWE & CAPEC)

CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorises the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-19027 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-19027 weaknesses.

Attack Vector and Accessibility

ExposureYerel erişim
PermissionsGerekmiyor
User—

Official Sources and Advisories

CVSS Vector Radar Chart

6.9 / 10
Attack VectorLocalComplexityLowPrivilegesNoneUser Interact.RequiredConfidentialityLowIntegrityNoneAvailabilityHigh

Vulnerability Scoring Details

CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N
Attack VectorLocal
Attack ComplexityLow
Privileges RequiredNone required
User InteractionP
Confidentiality (Gizlilik)Low
Integrity (Bütünlük)P
Availability (Erişilebilirlik)High

Yama durumu bilinmiyor

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Weakness Type (CWE & CAPEC)

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Get this vulnerability through the API

Affected products, version ranges, exploitation status and patch information in a single request, with a free key.

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  "https://api.enginteksut.com.tr/api/v1/intel/cves/CVE-2026-19027"