CVE-2021-3323 json
Integer Underflow in 6LoWPAN IPHC Header Uncompression in Zephyr
published 2021-10-12 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-26654
- cvss
- 8.3
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.9%
- EPSS 0.9% chance of exploitation in 30 days, percentile 60%
- public exploits
- 0
- none known
Summary
Integer Underflow in 6LoWPAN IPHC Header Uncompression in Zephyr. Zephyr versions >= >=2.4.0 contain Integer Underflow (Wrap or Wraparound) (CWE-191). For more information, see https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-89j6-qpxf-pfpc
Patch / fix
- zephyrproject zephyr 2.5.0
Exploit prediction
0.92% chance of exploitation in the next 30 days, higher than 60% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- github.com http://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-89j6-qpxf-pfpc referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 8.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:L |
| NVD | 3.1 | 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| NVD | 2.0 | 7.5 | AV:N/AC:L/Au:N/C:P/I:P/A:P |
Affected products
- zephyrproject-rtos zephyr
Classification
- Weakness
-
- CWE-191 Integer Underflow (Wrap or Wraparound)
References
-
github.com
/zephyrproject-rtos/zephyr/security/advisories/GHSA-89j6-qpxf-pfpc
exploit, patch, third-party-advisory
Sources
- CVE List CVE-2021-3323
- NVD CVE-2021-3323
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