Buffer Overflow vulnerability in function H5S_close in H5S.c in HDF5 1.10.4 allows remote attackers to run arbitrary code via creation of c…

published 2023-08-22 3 y ago modified 2026-06-17 4 mo ago also EUVD-2020-10418

cvss: 8.8; version 3.1, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 1.0%; EPSS 1.0% chance of exploitation in 30 days, percentile 63%
public exploits: 0; none known

Buffer Overflow vulnerability in function H5S_close in H5S.c in HDF5 1.10.4 allows remote attackers to run arbitrary code via creation of crafted file.

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2020-18494 updated 2025-11-21 cvss 7.8

hdf5: Buffer overflow in function H5S_close at H5S.c

Red Hat OpenStack Platform 16.1 hdf5
affected: no fix planned “Will not fix”

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation: Proof of concept is public
Automatable: no
Technical impact: total
Assessed: 2 y ago (2024-10-07)

Exploit prediction

1.01% chance of exploitation in the next 30 days, higher than 63% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

github.com https://github.com/magicSwordsMan/PAAFS/tree/master/vul12 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
NVD	3.1	8.8	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Classification

Weakness

CWE-787 Out-of-bounds Write

References

github.com /magicSwordsMan/PAAFS/tree/master/vul12
exploit, third-party-advisory

Sources

CVE List CVE-2020-18494
NVD CVE-2020-18494

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary