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: SMTP command and begin injecting arbitrary SMTP commands. It is recommended that Calendar is upgraded to 3.2.2. There are no workaround available.
CVE-2022-24838
MEDIUMNVD 5.35.5ElevatedEG-KEV Tier 3: ElevatedEG-KEV is EchelonGraph's own tiering of exploitation signals from CISA KEV, CISA's SSVC data (Vulnrichment), ransomware data, public exploit-code references and EPSS.Tier 3 is not evidence of exploitation. It means public exploit code is referenced, or CISA's SSVC data says "public PoC", or EPSS ranks the CVE in the top 5%.Signals for this CVE: EPSS in the top 5%.EchelonGraph confidence 38%: a heuristic from the tier and the number of signals, not a measured probability.
EchelonGraph scoreHIGH confidence
“▲” beside the score: it is higher than NVD's CVSS score.
Score elevated to 5.5 because EPSS predicted 33% probability of exploitation within the next 30 days (98th percentile of EPSS-scored CVEs) when EchelonGraph scored this CVE. NVD baseline CVSS 5.3 retained for reference. Confidence: see factors.
Triggered by: EPSS exploit prediction (continuous uplift above 30%)
Sources: EPSS, NVD CVSS v3
Also known asEUVD-2022-29623 (ENISA EUVD)Source: ENISA EUVD
5.5EG
EchelonGraph verdictMonitorNo release containing the referenced fix is confirmed: check the referenced fix and the vendor's advisory for a release that contains it; until one is applied, restrict network exposure of the affected system or apply the vendor's mitigation on your normal schedule at low or medium mission impact and sooner than that at high (the SSVC decision on this page).
- Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 33%CVSS: 5.3Exploit: No code on recordExposed services: Not assessed
A fix is referenced (a reference tagged "Patch", often a source commit), but no release containing it is confirmed — find the release that contains it; until it is applied, mitigate (WAF / firewall / segmentation).
- CVSS v3
- 5.3
- EG Score
- 5.5MEDIUMhigh confidence
- EG Risk
- 55EG Risk 55/100
EG Risk is EchelonGraph's 0–100 priority score. It fuses impact severity (EG Severity, the CVSS base score, never the KEV-floored or EPSS-lifted EG Score) with real-world exploitation and automatability, under weights EchelonGraph set by hand, so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner.
How it’s computed (value × EchelonGraph’s weight)Severity53% × 45%Impact severity (EG Severity): CVSS 5.3 of 10. Never the KEV-floored or EPSS-lifted EG Score.Exploitation40% × 40%EchelonGraph's fixed weight for EG-KEV Tier 3 (Elevated): a constant, not a probability.Automatability100% × 15%CISA's SSVC Automatable value: yes (Vulnrichment).SSVC (CISA's decision table, applied by EchelonGraph): Track at low or medium mission impact; Attend at high (mission-essential systems).Exploitation none (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE.Action: A fix is referenced, but no release containing it is confirmed. Check the referenced fix and the vendor's advisory for a release that contains it; until one is applied, restrict network exposure of the affected system or apply the vendor's mitigation on your normal schedule at low or medium mission impact and sooner than that at high. - EPSS PROB
- 33%
- EPSS %ILE
- 98th
- KEV
- Not listed
What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)
The EG score (5.5): severity, escalated by confirmed exploitation. This CVE's 5.5 is EPSS's lift toward 9.0 from its impact severity (EG Severity, CVSS 5.3 MEDIUM): a likelihood of exploitation, not impact.
- EG Severity
- 5.3 MEDIUMCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.NVD CVSS v3 · CVSS v3.0 or v3.1
- EG Likelihood
- 33% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-25). FIRST's exploitation probability, not an EchelonGraph model.
- Confirmed exploitation
- None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
- EG Priority
- SSVC Track at medium mission impactTrack at low or medium mission impact; Attend at high (mission-essential systems).CISA BOD 26-04: 14 days if the affected system is publicly exposed; 60 days if it is not.No released fix is confirmed on this page, but CISA's timeline does not wait for a fix's release: it starts when an agency identifies the flaw on an asset and updates the CDM Agency and Federal Dashboard, and the directive counts patching, decommissioning the system or another action as remediation. Until a fixed release is applied, mitigate as this page's verdict says.Each input and its source, and whom BOD 26-04 binds: the SSVC and BOD 26-04 blocks below.
SSVC (CISA's decision table, applied by EchelonGraph)Track at low or medium mission impact; Attend at high (mission-essential systems).
A fix is referenced, but no release containing it is confirmed. Check the referenced fix and the vendor's advisory for a release that contains it; until one is applied, restrict network exposure of the affected system or apply the vendor's mitigation on your normal schedule at low or medium mission impact and sooner than that at high.
Exploitation none (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table
BOD 26-04 (CISA's remediation timeline, Table 1)14 days if the affected system is publicly exposed; 60 days if it is not.
No released fix is confirmed on this page, but CISA's timeline does not wait for a fix's release: it starts when an agency identifies the flaw on an asset and updates the CDM Agency and Federal Dashboard, and the directive counts patching, decommissioning the system or another action as remediation. Until a fixed release is applied, mitigate as this page's verdict says.
The score's inputs: In CISA KEV no (CISA's KEV catalog) · Automatable yes (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it
Published
April 11, 2022
Last Modified
November 21, 2024
References (3)
- security-advisories@github · CVE Programhttps://github.com/nextcloud/calendar/commit/7b70edfb8a0fcf0926f613ababcbd56c6ecd9f35Patch · Third Party Advisory
- security-advisories@github · CVE Programhttps://github.com/nextcloud/calendar/pull/4073Patch · Third Party Advisory
- security-advisories@github · CVE Programhttps://github.com/nextcloud/security-advisories/security/advisories/GHSA-8xv5-4855-24qfThird Party Advisory
Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Related CVEs(same CWE)
Same CWE
10 shownCWE-74
- CVE-2022-24832EG 8.2HIGH
- CVE-2022-1287NVD 6.5EG 9.8CRITICAL
- CVE-2022-28345EG 7.5HIGH
- CVE-2022-20693NVD 4.7EG 7.2HIGH
- CVE-2022-20718NVD 5.5EG 7.2HIGH
- CVE-2022-20719NVD 5.5EG 7.2HIGH
- CVE-2021-39114EG 8.8HIGH
- CVE-2022-27924NVD 7.5EG 9.0 KEVEPSS p100CRITICAL
- CVE-2022-22965EG 9.8 KEVEPSS p100CRITICAL
- CVE-2022-24440EG 8.1HIGH
Frequently asked(5)
What is CVE-2022-24838?
CVE-2022-24838 is a medium-severity vulnerability; its CVE record was published on April 11, 2022. 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…
When was the CVE record for CVE-2022-24838 published?
The CVE record for CVE-2022-24838 was published on April 11, 2022. That is the record's publication date; the vulnerability itself may have been made public earlier. EchelonGraph's copy of the record carries a last-modified date of November 21, 2024; the record at its source may have been updated since.
Is CVE-2022-24838 actively exploited?
CVE-2022-24838 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 33% probability of exploitation in the next 30 days (98th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2022-24838?
CVE-2022-24838 has a CVSS v3 base score of 5.3 (NVD). EchelonGraph synthesises NVD + FIRST EPSS into a combined EG score of 5.5 (MEDIUM).
How do I remediate CVE-2022-24838?
A fix for CVE-2022-24838 is referenced (a reference tagged "Patch", often a source commit), but EchelonGraph has no release containing it on record. Check that reference and the vendor's advisory for a release that contains the fix and update to it; until then, restrict network exposure of the affected system or apply the vendor's mitigation.
Dependency Blast Radius
Explore the affected products and dependency analysis for CVE-2022-24838
Is Your Infrastructure Affected by CVE-2022-24838?
EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.