CVE-2026-31974 | Blind SSRF on OpenProject instance via webhooks

OpenProject is an open-source, web-based project management software. Prior to 17.2.0, OpenProject SMTP test endpoint (POST /admin/settings/mail_notifications) accepts arbitrary host and port values and exhibits measurable differences in response behaviour depending on whether the target IP exists and whether the port is open. An attacker with access can use these timing and error distinctions to map internal hosts and identify which services/ports are reachable. Similarly, you can create webhooks in OpenProject and point them to arbitrary IPs, resulting in the same kind of SSRF issue which allows attackers to scan the internal network. This vulnerability is fixed in 17.2.0.

Published: 2026-03-11 Last update: 2026-03-23 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-31974 is rated Low Risk (14.1/100): CVSS Low severity, with low exploitation likelihood (EPSS 0.02%). Low composite risk—no urgent action required; patch on your normal maintenance cycle and revisit priority if CVSS or EPSS increases.

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-2026-31974

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 2026-03-12 — 0.02% —

Full EPSS history (1 record total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-31974

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
3.0 3.1 LOW
CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:L/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:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:H)
They need powerful rights—admin, root, or similar—before this pays off.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
 1.3 1.4 [email protected]
4.3 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/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:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
 2.8 1.4 [email protected]

Weakness enumeration for CVE-2026-31974

Affected software / configurations for CVE-2026-31974

Vendor Product Version Raw CPE
openproject openproject < 17.2.0 cpe:2.3:a:openproject:openproject:*:*:*:*:*:*:*:*

References for CVE-2026-31974

cvelogic Threat Intelligence