CVE-2024-52520 | Nextcloud Server's link reference provider can be tricked into downloading bigger files than intended

Nextcloud Server is a self hosted personal cloud system. Due to a pre-flighted HEAD request, the link reference provider could be tricked into downloading bigger websites than intended, to find open-graph data. It is recommended that the Nextcloud Server is upgraded to 28.0.10 or 29.0.7 and Nextcloud Enterprise Server is upgraded to 27.1.11.8, 28.0.10 or 29.0.7.

Published: 2024-11-15 Last update: 2026-06-17 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2024-52520 is rated Moderate Risk (40.1/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 0.78%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2024-52520

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 1.33% 0.78% -0.55%
2 2026-03-04 1.16% 1.33% +0.16%
3 2026-03-01 — 1.16% —

Full EPSS history (26 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2024-52520

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.7 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 2.1 3.6 [email protected]
6.5 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
 2.8 3.6 [email protected]

Weakness enumeration for CVE-2024-52520

Affected software / configurations for CVE-2024-52520

Vendor Product Version Raw CPE
nextcloud nextcloud_server >= 27.0.0, < 27.1.11.8 cpe:2.3:a:nextcloud:nextcloud_server:*:*:*:*:enterprise:*:*:*
nextcloud nextcloud_server >= 28.0.0, < 28.0.10 cpe:2.3:a:nextcloud:nextcloud_server:*:*:*:*:-:*:*:*
nextcloud nextcloud_server >= 28.0.0, < 28.0.10 cpe:2.3:a:nextcloud:nextcloud_server:*:*:*:*:enterprise:*:*:*
nextcloud nextcloud_server >= 29.0.0, < 29.0.7 cpe:2.3:a:nextcloud:nextcloud_server:*:*:*:*:-:*:*:*
nextcloud nextcloud_server >= 29.0.0, < 29.0.7 cpe:2.3:a:nextcloud:nextcloud_server:*:*:*:*:enterprise:*:*:*

References for CVE-2024-52520

cvelogic Threat Intelligence