CVE-2026-122330
Blosc c-blosc2 before 3.5.0 Divide-by-Zero via blosc2_schunk_get_slice_buffer()
CVSS Score
5.5
EPSS Score
0.0%
EPSS Percentile
0th
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.
| CWE | CWE-369 |
| Vendor | blosc |
| Product | c-blosc2 |
| Published | Nov 5, 2026 |
| Last Updated | Nov 5, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H Attack Vector
Local
Attack Complexity
Low
Privileges Required
None
User Interaction
Required
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High
Affected Versions
Blosc / c-blosc2
0 < 3.5.0
References
github.com: https://github.com/Blosc/c-blosc2/issues/834 github.com: https://github.com/Blosc/c-blosc2/commit/4fff1787408d94b895c6f9cb50f7925ad5919052 github.com: https://github.com/Blosc/c-blosc2/blob/v3.4.1/blosc/schunk.c#L1662-L1700 github.com: https://github.com/Blosc/c-blosc2/blob/v3.4.1/blosc/frame.c#L1214-L1227 hackmd.io: https://hackmd.io/@haindpwn/c-blosc2-schunk-slice-divide-by-zero github.com: https://github.com/Blosc/c-blosc2 vulncheck.com: https://www.vulncheck.com/advisories/blosc-c-blosc2-before-3.5.0-divide-by-zero-via-blosc2-schunk-get-slice-buffer hackmd.io: https://hackmd.io/@haindpwn/cve-2026-122330-c-blosc2-schunk-slice-divide-by-zero
Credits
HaiND from the Post and Telecommunication Institute of Technology Francesc Alted