How severe is CVE-2022-24838?

CVE-2022-24838 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.

Is CVE-2022-24838 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 32% (98th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2022-24838?

CVE-2022-24838 affects Nextcloud Calendar. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2022-24838?

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

When was CVE-2022-24838 published?

CVE-2022-24838 was published on 2022-04-11 and last updated on 2026-06-17.

CVE-2022-24838

CVE-2022-24838 is a medium-severity vulnerability in Nextcloud Calendar with a CVSS 3.x base score of 5.3. Its EPSS exploit-prediction score of 32% places it in the 98th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-74.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
CVSS v2: 7.5
EPSS exploit prediction: 32% (98th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-74
Affected product: Nextcloud Calendar
Published: 2022-04-11
Last modified: 2026-06-17

Description

Nextcloud Calendar is a calendar application for the nextcloud framework. SMTP Command Injection in Appointment Emails via Newlines: as newlines and special characters are not sanitized in the email value in the JSON request, a malicious attacker can inject newlines to break out of the `RCPT TO:<BOOKING USER'S EMAIL> ` SMTP command and begin injecting arbitrary SMTP commands. It is recommended that Calendar is upgraded to 3.2.2. There are no workaround available.

Frequently asked questions

What is CVE-2022-24838?: Nextcloud Calendar is a calendar application for the nextcloud framework. SMTP Command Injection in Appointment Emails via Newlines: as newlines and special characters are not sanitized in the email value in the JSON request, a malicious attacker can inject newlines to break out of the `RCPT TO:<BOOKING USER'S EMAIL> ` SMTP command and begin injecting arbitrary SMTP commands. It is recommended that Calendar is upgraded to 3.2.2. There are no workaround available.
How severe is CVE-2022-24838?: CVE-2022-24838 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.
Is CVE-2022-24838 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 32% (98th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2022-24838?: CVE-2022-24838 affects Nextcloud Calendar. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2022-24838?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2022-24838 published?: CVE-2022-24838 was published on 2022-04-11 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:nextcloud:calendar:*:*:*:*:*:*:*:*

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