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NVD / CVE Program· CNA GitHub_M

CVE-2024-37887: Nextcloud Server's events information leaked with shared calendars on recurrence exceptions

LowCVSS 3.5 · v3.1—No exploit No fix recorded

Noroxi assessment

Priority: Monitor (action score 14/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 0.38% (FIRST EPSS).
  • Anyone who can reach it over the internet can trigger it. A low-privileged account is enough. A user must open a link or visit a page. No special conditions are required; it is repeatable.
  • No fixed version is recorded, but the references include a patch (commit or PR) link.

Low priority for now. See the fix and affected versions sections below.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

Nextcloud Server is a self hosted personal cloud system. Private shared calendar events' recurrence exceptions can be read by sharees. It is recommended that the Nextcloud Server is upgraded to 27.1.10 or 28.0.6 or 29.0.1 and that the Nextcloud Enterprise Server is upgraded to 27.1.10 or 28.0.6 or 29.0.1.

Published
Jun 14, 2024
Updated
Jun 17, 2026
EPSS
0.3% · 32th percentile

Report tools

JSON

Action score

14

Monitor

Low priority for now.

CVSS
14 / 40 · 3.5 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.3%

CISA SSVC decision

Exploitation
none
Automatable
no
Technical impact
partial

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD
3.5
CNA · GitHub_M
3.5
agree

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • No fixed version yet

If any of these changes, we'll tell you in the daily email digest.

Follow CVE-2024-37887

When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

VendorProduct
nextcloudnextcloud server

Versions reported by the vendor

Affected version ranges reported by the assigning authority (GitHub_M). Independent of NVD's CPE analysis and usually ahead of it.

  • nextcloud security-advisories

    • >= 27.0.0, < 27.1.10, >= 27.0.0, < 28.0.6, >= 27.0.0, < 29.0.1affected
Affected versions · NVD (4)

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • nextcloud nextcloud server27.0.0 and later · before 27.1.10
  • nextcloud nextcloud server28.0.0 and later · up to 28.0.6 inclusive
  • nextcloud nextcloud server28.0.0 and later · before 28.0.6
  • nextcloud nextcloud server29.0.0

Same product

nextcloud: all records

Other highest-scoring records for the same primary product.

  • CVE-2023-26482Scope of workflow operations is not validated in nextcloud server
    40Plan
  • CVE-2021-32802Preview generation used third-party library not suited for user-generated content in Nextcloud server
    40Plan
  • CVE-2021-32726Webauthn tokens not removed after user has been deleted
    40Plan

Published before and after this one in the same product

  • ← EarlierCVE-2024-37882Jun 14, 2024 · Nextcloud Server can reshare read&share only folder with more permissions
    32Monitor
  • ← EarlierCVE-2024-37884Jun 14, 2024 · Nextcloud Server's users can delete old versions of read-only shared files
    21Monitor
  • Later →CVE-2024-52515Nov 15, 2024 · Nextcloud Server has incomplete sanitization of SVG files allows to embed other images into previews
    26Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

No fix version is recorded for this entry. Check the references for vendor advisories.

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

  • CVE-2024-378820 days apartNextcloud Server can reshare read&share only folder with more permissions
    32Monitor
  • CVE-2023-35927357 days apartNextcloud system addressbooks can be modified by malicious trusted server
    32Monitor
  • CVE-2023-39963309 days apartMissing password confirmation when creating app passwords
    31Monitor
  • CVE-2023-39962309 days apartUsers can delete external storage mount points
    30Monitor
  • CVE-2023-25821476 days apartNextcloud download permissions can be changed by resharer
    30Monitor
  • CVE-2023-48239206 days apartNextcloud Server users can make external storage mount points inaccessible for other users
    28Monitor

Bug bounty scope

The product’s vendor appears in a public program. Matched by name; verify the scope text in the program.

Not on record for this CVE: EPSS history · researcher credit.

Technical details

Attack conditions

  • Anyone who can reach it over the internet can trigger it.
  • A low-privileged account is enough.
  • A user must open a link or visit a page.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
low · data can be read
Integrity
none
Availability
none
Attack vector
Network
Attack complexity
Low
Privileges required
Low
User interaction
Required
Scope
Unchanged
Confidentiality impact
Low
Integrity impact
None
Availability impact
None

Weakness class (CWE)

CWE-284 · Improper Access Control

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:N/A:N

nvd-primary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

References

Show all references (2 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records