CVE-2026-120755

Read full description

HDF5 through 2.2.0 contains an out-of-bounds read vulnerability in H5Z__filter_szip() in src/H5Zszip.c. When decoding a szip-compressed chunk, the function subtracts the 4-byte uncompressed-length header from the chunk length without first verifying that the chunk is at least 4 bytes long. A truncated or corrupted chunk shorter than the header causes the length calculation to wrap around to a very large value, and the decompressor reads far past the end of the chunk buffer. An attacker who can get a user or application to read a dataset from a crafted HDF5 file can cause a denial of service. Only builds with szip support (libaec or the szip library) are affected.

CVSS 4.7 (MEDIUM)

Attention and evidence

HYPE SCORE

0.0/10

REALITY · THREAT PRIORITY

1.6/10

General review priority; not probability

Evidence confidence: Insufficient evidence

Why this priority?

Technical severity: CVSS 4.7: +1.65
Fresh EPSS: 0.14%: +0.00

General review priority, not probability, victim count or asset-specific risk. A range covers missing CVSS/EPSS inputs within the current evidence state.

Based on public data to date.

Hype components

Headline sample (25%)

0/100

Press, 30 days (60%)

0/100

Grounded branding (15%)

0/100

HYPE TOTAL0/100

Sources and documents

No source documents yet.

Score evolution

● Hype ● Reality

First record: hype 0.0 · reality 1.6 (2026-11-04 13:50). The curve appears once the score changes.

Public exploit evidence

Public exploit entries / repo candidates

Evidence context and dated references

Reality is general threat/review priority, combining observed exploitation, CVSS severity and fresh EPSS. Evidence confidence is separate. This is not calibrated risk, a victim count or an asset-specific assessment. A range reflects missing numeric inputs. Published 4 days ago. Exploitation evidence usually takes weeks to show up: a low reality score can mean there is no data yet, not that the flaw is mild.

Evidence in context

Confidence in exploitation evidence: Insufficient evidence
Priority basis: Exploitation in attacks unconfirmed; CVSS 4.7; EPSS 0.1%
Attention, last 30 days: 0 distinct story titles; 0 press documents; 0 publisher domains.
Technical potential: local access, no prior privileges, passive user interaction, additional attack conditions.
Observed activity: No exploitation observation is recorded.
Known scale: Not quantified.
Evidence confidence basis: Insufficient evidence

Score evaluated: 2026-11-05 13:59:56.876805+00:00 · EPSS snapshot: 2026-11-05T12:03:04Z

Source event timeline

Published

03 Nov 2026, 15:27

Score calculated

05 Nov 2026, 13:59