CVE-2021-40439 json
Billion Laughs
published 2021-10-07 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-27616
- cvss
- 6.5
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 3.9%
- EPSS 3.9% chance of exploitation in 30 days, percentile 90%
- public exploits
- 0
- none known
Summary
Apache OpenOffice has a dependency on expat software. Versions prior to 2.1.0 were subject to CVE-2013-0340 a "Billion Laughs" entity expansion denial of service attack and exploit via crafted XML files. ODF files consist of a set of XML files. All versions of Apache OpenOffice up to 4.1.10 are subject to this issue. expat in version 4.1.11 is patched.
Exploit prediction
3.87% chance of exploitation in the next 30 days, higher than 90% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 3.1 | 6.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H |
| NVD | 2.0 | 4.3 | AV:N/AC:M/Au:N/C:N/I:N/A:P |
Affected products
- Apache Software Foundation Apache OpenOffice
Classification
- Weakness
-
- CWE-611 Improper Restriction of XML External Entity Reference
References
-
lists.apache.org
/thread.html/rfb2c193360436e230b85547e85a41bea0916916f96c501f5b6fc4702%40%3Cusers.openoffice.apache.org%3E
mailing-list, vendor-advisory
-
lists.apache.org
/thread.html/r41eca5f4f09e74436cbb05dec450fc2bef37b5d3e966aa7cc5fada6d%40%3Cannounce.apache.org%3E
mailing-list
-
openwall.com
/lists/oss-security/2021/10/07/4
mailing-list, third-party-advisory
Sources
- CVE List CVE-2021-40439
- NVD CVE-2021-40439
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.