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 v3 5.5 MEDIUM

5.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
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

Configurations

No configuration.

History

14 Oct 2026, 21:17

Type	Values Removed	Values Added
References	~~() https://github.com/brechtsanders/xlsxio/issues/151 -~~	() https://github.com/brechtsanders/xlsxio/issues/151 -
References	~~() https://hackmd.io/@haind-pwn/xlsxio-relationship-missing-id-null-deref -~~	() https://hackmd.io/@haind-pwn/xlsxio-relationship-missing-id-null-deref -

14 Oct 2026, 15:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-14 15:17

Updated : 2026-10-15 14:47

NVD link : CVE-2026-110600

Mitre link : CVE-2026-110600

CVE.ORG link : CVE-2026-110600

JSON object : View

Products Affected

No product.

CWE

CWE-476

NULL Pointer Dereference

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