CVE-2026-110600
xlsxio through 0.2.37 contains a NULL pointer dereference vulnerability in main_sheet_get_sheetfile_expat_callback_element_start() in lib/xlsxio_read.c that allows attackers to crash applications via crafted files. Attackers can supply a .xlsx file whose workbook.xml.rels contains a worksheet Relationship lacking an Id attribute, crashing the process when xlsxioread_sheet_open() is called.
CVSS
- Version: 4.0
- Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
- Base score: 6.8
Exploitation probability (EPSS)
- Probability of exploitation in the next 30 days: 0.24%
- Percentile among all scored CVEs: 14
- Score date: 10/18/2026
EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).
🎯 ATT&CK techniques
How this vulnerability is exploited and what the attacker gains, in MITRE ATT&CK terms.
- Exploitation
T1203Exploitation for Client Executionexecution55 % - Primary impact
T1499Endpoint Denial of Serviceimpact85 %
El vector AV:L con UI:P indica que el usuario debe abrir un .xlsx manipulado; el texto describe un crash del proceso al llamar a xlsxioread_sheet_open(), lo que encaja con DoS.
Inferred by our analysis agent from the official description, CVSS vector and CWE, and checked by a supervisor. May contain errors.
🛡️ ATT&CK mitigations that cover these techniques
Affected technologies (1)
⚠ AI-inferred from the description — NVD hasn't analyzed this CVE yet, these aren't verified CPEs.
CWEs
- CWE-476
References
- https://github.com/brechtsanders/xlsxio/blob/0.2.37/lib/xlsxio_read.c#L851-L866
- https://github.com/brechtsanders/xlsxio/issues/151
- https://hackmd.io/@haind-pwn/xlsxio-relationship-missing-id-null-deref
- https://www.vulncheck.com/advisories/xlsxio-through-0.2.37-null-pointer-dereference-via-worksheet-relationship-without-id
- https://github.com/brechtsanders/xlsxio/issues/151
- https://hackmd.io/@haind-pwn/xlsxio-relationship-missing-id-null-deref
Raw JSON (NVD)
Show
{
"id": "CVE-2026-110600",
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"metrics": {
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"timestamp": "2026-10-14T20:43:41.729380Z"
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"vulnAvailabilityImpact": "HIGH",
"availabilityRequirement": "NOT_DEFINED",
"modifiedUserInteraction": "NOT_DEFINED",
"modifiedAttackComplexity": "NOT_DEFINED",
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"vulnConfidentialityImpact": "NONE",
"confidentialityRequirement": "NOT_DEFINED",
"modifiedAttackRequirements": "NOT_DEFINED",
"modifiedPrivilegesRequired": "NOT_DEFINED",
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"modifiedVulnIntegrityImpact": "NOT_DEFINED",
"vulnerabilityResponseEffort": "NOT_DEFINED",
"modifiedSubAvailabilityImpact": "NOT_DEFINED",
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"affected": [
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"affectedData": [
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"repo": "https://github.com/brechtsanders/xlsxio",
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"versions": [
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"published": "2026-10-14T15:17:11.387",
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"descriptions": [
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"value": "xlsxio through 0.2.37 contains a NULL pointer dereference vulnerability in main_sheet_get_sheetfile_expat_callback_element_start() in lib/xlsxio_read.c that allows attackers to crash applications via crafted files. Attackers can supply a .xlsx file whose workbook.xml.rels contains a worksheet Relationship lacking an Id attribute, crashing the process when xlsxioread_sheet_open() is called."
}
],
"lastModified": "2026-10-15T14:47:05.720",
"sourceIdentifier": "disclosure@vulncheck.com"
}