CVE-2021-33035
HighExploitedApache OpenOffice opens dBase/DBF documents and shows the contents as spreadsheets.
Published Oct 12, 2021 · Updated Aug 4, 2026 · Also known as DEBIAN-CVE-2021-33035, TR-21-0775, UBUNTU-CVE-2021-33035
Key Facts
Patch immediately- CVE-2021-33035 is a high-severity vulnerability (CVSS 7.8 v3.1) affecting Openoffice (Apache), libreoffice (debian).
- It is exploited in the wild, listed in Industry KEV feed since May 2, 2023. No public exploit code is known.
- EPSS estimates a 51% probability of exploitation in the next 30 days.
- Fixed versions are available, including Openoffice <=4.1.10, libreoffice 1:4.3.1-1, Openoffice 4.1.10.
- Brandefense priority: patch immediately, because it is listed as exploited in the wild.
CVSS v3.1
7.8
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
EPSS (30-day exploit likelihood)
51%
Higher than 98.9% of all scored CVEs
Exploited in the wild
Yes
1 catalog listing
Public exploit code
None known
Get the full CVE-2021-33035 brief as a PDF
Every affected product and fixed release, exploitation status and a first 24 hours response checklist, emailed within minutes.
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
Known-Exploited Catalog Listings
| Catalog | Added | Remediation due | Ransomware use |
|---|---|---|---|
| Industry KEV feed | May 2, 2023 | n/a | Not reported |
Required action: Apply remediations or mitigations per vendor instructions or discontinue use of the product if remediation or mitigations are unavailable.
Affected Products
13 affected entries in total| Product | Affected versions | Fixed in |
|---|---|---|
| OpenofficeApache | >= Apache OpenOffice | 4.1.10 |
| libreofficedebian | See advisory | 1:4.3.1-1 |
Patched Releases
Openoffice
<=4.1.10
libreoffice
1:4.3.1-1
Timeline
Publicly disclosed
Oct 12, 2021
Added to Industry KEV feed
May 2, 2023
Last updated
Aug 4, 2026
Weakness Type
- CWE-120 Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')
References
- advisoryhttp://github.com/apache/openoffice/commit/efddaef0151af3be16078cc4d88c6bae0f911e56#diff-ea66e734dd358922aba12ad4ba39c96bdc6cbde587d07dbc63d04daa0a30e90f
- advisoryhttp://lists.apache.org/thread.html/r1ab8532e11f41bc7ca057ac7e39cab25f2e1f9d5f4929788ae21c8b9@%3Cusers.openoffice.apache.org%3E
- advisoryhttp://lists.apache.org/thread.html/r929c0c6a53cad64a1007b878342756badbb05ddd9b8f31a6d0b424cb@%3Cannounce.apache.org%3E
- advisoryhttps://security-tracker.debian.org/tracker/CVE-2021-33035
- advisoryhttps://ubuntu.com/security/CVE-2021-33035
FAQ
Common Questions.
Apache OpenOffice opens dBase/DBF documents and shows the contents as spreadsheets.
Affected: Openoffice (Apache) versions >= Apache OpenOffice; libreoffice (debian). The full list is in the CVE brief.
It is exploited in the wild, listed in Industry KEV feed since May 2, 2023.
No, it is not currently listed in the CISA Known Exploited Vulnerabilities catalog.
No public exploit code is known.
Fixed versions are available, including Openoffice <=4.1.10, libreoffice 1:4.3.1-1, Openoffice 4.1.10.
Brandefense priority: patch immediately, because it is listed as exploited in the wild.
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