CVE-2026-122330

EUVD-2026-117538
Blosc c-blosc2 before 3.5.0 contains a divide-by-zero vulnerability in blosc2_schunk_get_slice_buffer() in blosc/schunk.c that allows attackers to crash applications by supplying crafted frames with unchecked zero chunksize or blocksize values. Attackers can provide a malicious Blosc2 frame opened via blosc2_schunk_open() or blosc2_schunk_from_buffer() and read as a slice, raising SIGFPE and terminating the process.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
VulnCheckCNA
5.5 MEDIUM
LOCAL
LOW
NONE
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
Base Score
CVSS 3.x
EPSS Score
Percentile: Unknown
Early Detection
Affected products identified ahead of NVD analysis through intelligence sources (CNA/ADP records, vendor advisories, Enginsight analysis).
VendorProductVersionSource
bloscc-blosc2
𝑥
< 3.5.0
CNA
Common Weakness Enumeration
References
https://github.com/Blosc/c-blosc2
https://github.com/Blosc/c-blosc2/blob/v3.4.1/blosc/frame.c#L1214-L1227
https://github.com/Blosc/c-blosc2/blob/v3.4.1/blosc/schunk.c#L1662-L1700
https://github.com/Blosc/c-blosc2/commit/4fff1787408d94b895c6f9cb50f7925ad5919052
https://github.com/Blosc/c-blosc2/issues/834
https://hackmd.io/@haindpwn/c-blosc2-schunk-slice-divide-by-zero
https://www.vulncheck.com/advisories/blosc-c-blosc2-before-3.5.0-divide-by-zero-via-blosc2-schunk-get-slice-buffer
https://hackmd.io/@haindpwn/cve-2026-122330-c-blosc2-schunk-slice-divide-by-zero