Blosc c-blosc2 up to 3.4.x Chunk blosc/schunk.c blosc2_schunk_get_slice_buffer divide by zero

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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4.1$0-$5k0.00+

Summaryinfo

A vulnerability described as problematic has been identified in Blosc c-blosc2 up to 3.4.x. The affected element is the function blosc2_schunk_get_slice_buffer of the file blosc/schunk.c of the component Chunk Handler. Such manipulation leads to divide by zero. This vulnerability is uniquely identified as CVE-2026-122330. Local access is required to approach this attack. No exploit exists. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability was found in Blosc c-blosc2 up to 3.4.x and classified as problematic. Affected by this issue is the function blosc2_schunk_get_slice_buffer of the file blosc/schunk.c of the component Chunk Handler. The manipulation with an unknown input leads to a divide by zero vulnerability. Using CWE to declare the problem leads to CWE-369. The product divides a value by zero. Impacted is availability. CVE summarizes:

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.

The advisory is shared for download at github.com. This vulnerability is handled as CVE-2026-122330 since 11/05/2026. The exploitation is known to be easy. The attack needs to be approached locally. Successful exploitation requires user interaction by the victim. There are known technical details, but no exploit is available.

Upgrading to version 3.5.0 eliminates this vulnerability.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Vendor

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 4.1
VulDB Meta Temp Score: 4.1

VulDB Base Score: 2.8
VulDB Temp Score: 2.7
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 5.5
CNA Vector (VulnCheck): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Divide by zero
CWE: CWE-369 / CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: c-blosc2 3.5.0

Timelineinfo

11/05/2026 Advisory disclosed
11/05/2026 +0 days CVE reserved
11/05/2026 +0 days VulDB entry created
11/05/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Confirmed

CNA: VulnCheck
CVE: CVE-2026-122330 (🔒)

GCVE (CVE): GCVE-0-2026-122330
GCVE (VulDB): GCVE-100-431492

Entryinfo

Created: 11/05/2026 16:31
Changes: 11/05/2026 16:31 (78)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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