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Fencer Intel
medium 5.3

CVE-2026-121562 json

CTFd 3.1.0 before 3.8.7 Information Disclosure via /api/v1/teams Endpoint

published 6d ago modified 10h ago also EUVD-2026-115907

cvss
5.3
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.3%
EPSS 0.3% chance of exploitation in 30 days, percentile 25%
public exploits
0
none known

Summary

CTFd 3.1.0 before 3.8.7 contains an information disclosure vulnerability in the /api/v1/teams list endpoint that exposes non-public team custom field values. Unauthenticated attackers can paginate GET requests to collect hidden registration data such as emails, phone numbers, and student IDs when team mode and public visibility are enabled.

Patch / fix

  • CTFd CTFd 3.8.7

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CISA SSVC

Exploitation
none
Automatable
yes
Technical impact
partial
Assessed
11h ago

Exploit prediction

0.33% chance of exploitation in the next 30 days, higher than 25% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by version score vector
CNA 4.0 6.9 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N
CNA 3.1 5.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
CNA 4.0 6.9 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/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:X

Affected products

  • CTFd CTFd

Classification

Weakness

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.