Vulnerability · CVE-2021-33035
Apache openoffice Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')
Published May 2, 2023 · catalog updated May 2, 2023 · Apache
Patch now
CVE-2021-33035 is in the CISA known-exploited catalog. Confirm Apache against the vendor advisory and apply that fix. The CVSS score does not change the priority.
Gaps on this record
- No version range is stored. A customer cannot check an installed version against this record.
- Severity
- Unknown—
- Known exploitation
- CISA KEV and VulnCheck KEV
- EPSS
- 50.56%
- Remediation
- Remediation guidance
- Affected products
- vendor Apache openoffice
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
Are you affected?
Enter the version you run. The result uses only the ranges stored on this record.
The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.
- vendor Apache openofficeversion unspecified
How to fix CVE-2021-33035
Recommended remediation
Apply remediations or mitigations per vendor instructions or discontinue use of the product if remediation or mitigations are unavailable.
Official advisories
What to do
Three questions, each answered from this record only. Confirm the vendor advisory before you patch.
Should you patch?
CVE-2021-33035 is in the CISA known-exploited catalog. Confirm Apache against the vendor advisory and apply that fix. The CVSS score does not change the priority.
Which versions are affected?
Affected version ranges are not on this record. Apply remediations or mitigations per vendor instructions or discontinue use of the product if remediation or mitigations are unavailable.
What should an analyst verify?
No weakness class is stored. EPSS 50.56%. The CISA KEV listing is the exploitation evidence. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.
Code
The project this record applies to. Exploit listings stay in References.
No public source repository is identified for this product.
Timeline
Detection, updates, and resolution for this record.
May 2, 2023 · VulnCheck KEV
Detected
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 sta
May 2, 2023 · CISA KEV
Known exploited
Apply remediations or mitigations per vendor instructions or discontinue use of the product if remediation or mitigations are unavailable.
Sources
- CVE.orgVulnerability recordCVE-2021-33035
Official CVE identifier
cve.org - FIRST EPSSExploitation probabilityCVE-2021-33035
30-day exploitation probability 50.6%
first.org - VulnCheck KEVConfirmed exploitationCVE-2021-33035
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 co
vulncheck.com
References
Freshness
Last verified in this catalog Oct 18, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.