CVE-2021-40511 json
OBDA systems’ Mastro 1.0 is vulnerable to XML Entity Expansion (aka “billion laughs”) attack allowing denial of service.
published 2022-06-21 4 y ago modified 2026-06-17 4 mo ago also EUVD-2021-27687
- cvss
- 7.5
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.9%
- EPSS 0.9% chance of exploitation in 30 days, percentile 61%
- public exploits
- 0
- none known
Summary
OBDA systems’ Mastro 1.0 is vulnerable to XML Entity Expansion (aka “billion laughs”) attack allowing denial of service.
Exploit prediction
0.94% chance of exploitation in the next 30 days, higher than 61% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| NVD | 2.0 | 5.0 | AV:N/AC:L/Au:N/C:N/I:N/A:P |
Classification
- Weakness
-
- CWE-776 Improper Restriction of Recursive Entity References in DTDs
References
-
obdasystems.com
/mastro
product, vendor-advisory
-
cyberiskvision.com
/advisory/
third-party-advisory
Sources
- CVE List CVE-2021-40511
- NVD CVE-2021-40511
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