CVE-2021-20988 json
Hilscher rcX RTOS: Wrong handling of the UDP checksum
published 2021-05-13 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-8397
- cvss
- 8.6
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.0%
- EPSS 1.0% chance of exploitation in 30 days, percentile 62%
- public exploits
- 0
- none known
Summary
In Hilscher rcX RTOS versions prios to V2.1.14.1 the actual UDP packet length is not verified against the length indicated by the packet. This may lead to a denial of service of the affected device.
Patch / fix
- Hilscher rcX RTOS V2.1.14.1
Exploit prediction
0.99% chance of exploitation in the next 30 days, higher than 62% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 8.6 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H |
| 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 |
Affected products
- Hilscher rcX RTOS
- Pepperl+Fuchs Ethernet IO Modules ICE1-16
- Pepperl+Fuchs Ethernet IO Modules ICE1-8
Classification
- Weakness
-
- CWE-119 Improper Restriction of Operations within the Bounds of a Memory Buffer
References
-
kb.hilscher.com
/display/ISMS/2019-04-10+Wrong+handling+of+the+UDP+checksum
vendor-advisory
-
cert.vde.com
/de-de/advisories/vde-2021-018
third-party-advisory
Sources
- CVE List CVE-2021-20988
- NVD CVE-2021-20988
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