How severe is CVE-2021-38542?

CVE-2021-38542 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 high, integrity none, and availability none.

Is CVE-2021-38542 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (82nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-38542?

CVE-2021-38542 affects Apache James. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-38542?

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

When was CVE-2021-38542 published?

CVE-2021-38542 was published on 2022-01-04 and last updated on 2026-06-17.

CVE-2021-38542

CVE-2021-38542 is a medium-severity vulnerability in Apache James 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-327.

Key facts

Severity: Medium (CVSS 3.x base score 5.9)
CVSS v2: 4.3
EPSS exploit prediction: 2% (82nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-327
Affected product: Apache James
Published: 2022-01-04
Last modified: 2026-06-17

Description

Apache James prior to release 3.6.1 is vulnerable to a buffering attack relying on the use of the STARTTLS command. This can result in Man-in -the-middle command injection attacks, leading potentially to leakage of sensible information.

Frequently asked questions

What is CVE-2021-38542?: Apache James prior to release 3.6.1 is vulnerable to a buffering attack relying on the use of the STARTTLS command. This can result in Man-in -the-middle command injection attacks, leading potentially to leakage of sensible information.
How severe is CVE-2021-38542?: CVE-2021-38542 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 high, integrity none, and availability none.
Is CVE-2021-38542 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (82nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-38542?: CVE-2021-38542 affects Apache James. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-38542?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-38542 published?: CVE-2021-38542 was published on 2022-01-04 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:apache:james:*:*:*:*:*:*:*:*

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