CVE-2021-33035: Buffer overflow from a crafted DBF file

Severity: high (CVSS 7.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 50.6% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-09-23 · updated 2026-06-17
Weakness: CWE-120

Description

Apache OpenOffice opens dBase/DBF documents and shows the contents as spreadsheets. DBF are database files with data organized in fields. When reading DBF data the size of certain fields is not checked: the data is just copied into local variables. A carefully crafted document could overflow the allocated space, leading to the execution of arbitrary code by altering the contents of the program stack. This issue affects Apache OpenOffice up to and including version 4.1.10

Affected products

Apache Software Foundation Apache OpenOffice: through 4.1.10

References

http://www.openwall.com/lists/oss-security/2021/10/07/3
https://github.com/apache/openoffice/commit/efddaef0151af3be16078cc4d88c6bae0f911e56#diff-ea66e734dd358922aba12ad4ba39c96bdc6cbde587d07dbc63d04daa0a30e90f
https://lists.apache.org/thread.html/r1ab8532e11f41bc7ca057ac7e39cab25f2e1f9d5f4929788ae21c8b9%40%3Cusers.openoffice.apache.org%3E
https://lists.apache.org/thread.html/r929c0c6a53cad64a1007b878342756badbb05ddd9b8f31a6d0b424cb%40%3Cannounce.apache.org%3E
http://www.openwall.com/lists/oss-security/2021/10/07/3
https://github.com/apache/openoffice/commit/efddaef0151af3be16078cc4d88c6bae0f911e56#diff-ea66e734dd358922aba12ad4ba39c96bdc6cbde587d07dbc63d04daa0a30e90f
https://lists.apache.org/thread.html/r1ab8532e11f41bc7ca057ac7e39cab25f2e1f9d5f4929788ae21c8b9%40%3Cusers.openoffice.apache.org%3E
https://lists.apache.org/thread.html/r929c0c6a53cad64a1007b878342756badbb05ddd9b8f31a6d0b424cb%40%3Cannounce.apache.org%3E

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