What is CVE-2021-33983?

CVE-2021-33983 is a high-severity vulnerability in Flatcc Project, classified under Buffer Copy without Checking Size of Input (Classic Buffer Overflow). CVSS score: 7.8/10. Published 2023-02-17.

How severe is CVE-2021-33983?

High severity. CVSS v3 base score is 7.8 out of 10.

Is CVE-2021-33983 known to be exploited?

1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

Buffer overflow in Flatcc Project

CVE-2021-33983

Buffer Overflow vulnerability in Dvidelabs flatcc v.0.6.0 allows local attacker to execute arbitrary code via the fltacc execution of the error_ref_sym function.

Vulnerability class: Buffer Overflow

Published 2023-02-17 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.003 (21.8th percentile), scored 2026-10-01.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 22nd percentile — 21.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: 0.000

Affected products

Flatcc Project — versions 0.6.0

Weakness classification (CWE)

CWE-120 — Buffer Copy without Checking Size of Input (Classic Buffer Overflow)

Public proof-of-concept exploits

DiRaltvein/memory-corruption-examples

References

github.com/dvidelabs/flatcc/issues/188 (Exploit, Patch, Third Party Advisory, Issue Tracking)

Frequently asked questions

What is CVE-2021-33983?: CVE-2021-33983 is a high-severity vulnerability in Flatcc Project, classified under Buffer Copy without Checking Size of Input (Classic Buffer Overflow). CVSS score: 7.8/10. Published 2023-02-17.
How severe is CVE-2021-33983?: High severity. CVSS v3 base score is 7.8 out of 10.
Is CVE-2021-33983 known to be exploited?: 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.