How severe is CVE-2021-33833?

CVE-2021-33833 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-33833 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (85th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-33833?

CVE-2021-33833 primarily affects Intel Connection Manager. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-33833?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2021-33833 published?

CVE-2021-33833 was published on 2021-06-09 and last updated on 2026-06-17.

CVE-2021-33833

CVE-2021-33833 is a critical-severity vulnerability in Intel Connection Manager with a CVSS 3.x base score of 9.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-787.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 3% (85th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-787
Affected product: Intel Connection Manager
Published: 2021-06-09
Last modified: 2026-06-17

Description

ConnMan (aka Connection Manager) 1.30 through 1.39 has a stack-based buffer overflow in uncompress in dnsproxy.c via NAME, RDATA, or RDLENGTH (for A or AAAA).

Frequently asked questions

What is CVE-2021-33833?: ConnMan (aka Connection Manager) 1.30 through 1.39 has a stack-based buffer overflow in uncompress in dnsproxy.c via NAME, RDATA, or RDLENGTH (for A or AAAA).
How severe is CVE-2021-33833?: CVE-2021-33833 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-33833 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (85th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-33833?: CVE-2021-33833 primarily affects Intel Connection Manager. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-33833?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2021-33833 published?: CVE-2021-33833 was published on 2021-06-09 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:intel:connection_manager:*:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*

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