Raw vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:XSummary
CVE-2026-25738 is a medium-severity Time-of-check Time-of-use (TOCTOU) Race Condition (CWE-367) vulnerability in Cern Indico. Its CVSS base score is 6.9 (Medium).
Operationally, exploitation aligns with the MITRE ATT&CK technique Path Interception (T1034); ranked at the 9th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
The strongest mitigations our analysis identified map to AC-25 (Reference Monitor) and AC-4 (Information Flow Enforcement) — see the control section below for these in your framework.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-8107
Vulnerability Data
Indico is an event management system that uses Flask-Multipass, a multi-backend authentication system for Flask. Versions prior to 3.3.10 are vulnerable to server-side request forgery. Indico makes outgoing requests to user-provides URLs in various places. This is mostly intentional and…
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part of Indico's functionality but is never intended to let users access "special" targets such as localhost or cloud metadata endpoints. Users should upgrade to version 3.3.10 to receive a patch. Those who do not have IPs that expose sensitive data without authentication (typically because they do not host Indico on AWS) are not affected. Only event organizers can access endpoints where SSRF could be used to actually see the data returned by such a request. For those who trust their event organizers, the risk is also very limited. For additional security, both before and after patching, one may also use the common proxy-related environment variables (in particular `http_proxy` and `https_proxy`) to force outgoing requests to go through a proxy that limits requests in whatever way you deem useful/necessary. These environment variables would need to be set both on the indico-uwsgi and indico-celery services.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
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V15.4.2V17.2.6V1.3.6V1.5.3
Mitigating Controls (NIST 800-53 r5) AI
A reference monitor that is always invoked and analyzable structurally eliminates the non-atomic check-then-use pattern underlying TOCTOU.
Information flow enforcement can restrict which destinations the server is allowed to contact on behalf of users.
Input validation directly stops untrusted URLs from being accepted and fetched without destination checks.
Access enforcement that performs an atomic check-and-use decision directly stops the window in which a TOCTOU race can be exploited.
Process isolation limits the blast radius of a successful TOCTOU exploitation but does not remove the race itself.
Boundary protection limits the network reach of server-initiated requests even if SSRF occurs.
Mitigating Controls (NIST CSF 2.0) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.
Secure SDLC practices directly include coding standards and reviews that prevent TOCTOU race conditions.
Runtime monitoring of web applications and services can detect anomalous outbound requests indicative of SSRF.
Vulnerability identification processes can discover and record SSRF flaws in web applications.
Network segmentation and egress controls can limit the damage from successful SSRF requests.
Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.
Operational threat data describing SSRF campaigns can be used to tighten outbound-request allow-lists and detection rules before attackers exploit them.
Reliable, synchronized time across systems narrows the exploitable window in which a resource state can change between a security check and its use.