How severe is CVE-2021-46853?

CVE-2021-46853 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2021-46853 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (53rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-46853?

CVE-2021-46853 affects Alpine Project Alpine. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-46853?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-46853 published?

CVE-2021-46853 was published on 2022-11-03 and last updated on 2026-06-17.

CVE-2021-46853

CVE-2021-46853 is a medium-severity vulnerability in Alpine Project Alpine with a CVSS 3.x base score of 5.9. 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-367.

Key facts

Severity: Medium (CVSS 3.x base score 5.9)
EPSS exploit prediction: 1% (53rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-367
Affected product: Alpine Project Alpine
Published: 2022-11-03
Last modified: 2026-06-17

Description

Alpine before 2.25 allows remote attackers to cause a denial of service (application crash) when LIST or LSUB is sent before STARTTLS.

Frequently asked questions

What is CVE-2021-46853?: Alpine before 2.25 allows remote attackers to cause a denial of service (application crash) when LIST or LSUB is sent before STARTTLS.
How severe is CVE-2021-46853?: CVE-2021-46853 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2021-46853 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (53rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-46853?: CVE-2021-46853 affects Alpine Project Alpine. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-46853?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-46853 published?: CVE-2021-46853 was published on 2022-11-03 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:alpine_project:alpine:*:*:*:*:*:*:*:*

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