CVE-2026-103239 json
MISP Tag Collection Save Allows Privilege Escalation via Sibling Model Injection
published 2026-09-30 39 d ago modified 2026-09-30 39 d ago also EUVD-2026-89761
- cvss
- 8.6
- version 4.0, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 17%
- public exploits
- 0
- none known
Summary
MISP contains a privilege escalation vulnerability in the tag collection creation and editing functionality. The affected actions accepted the full HTTP request payload and passed it to a bulk-association save operation, which writes not only the intended tag collection record but also any associated model data present in the payload.
A user holding the tag editor permission could craft a request that includes additional model data (such as User or Organisation records) alongside the tag collection fields. Because the save operation processed all associated models indiscriminately, the injected sibling records were written to the database, enabling the attacker to modify or create privileged accounts and escalate to site administrator.
Preconditions:
- An authenticated account with the tag editor permission (perm_tag_editor)
- Network access to the MISP instance
Impact:
- Unauthorized creation or modification of User and Organisation records
- Privilege escalation from tag editor to site administrator
Affected versions: < 2.5.48
Patch / fix
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- total
- Assessed
- 39 d ago
Exploit prediction
0.26% chance of exploitation in the next 30 days, higher than 17% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 8.6 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N |
| CNA | 4.0 | 8.6 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/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
- MISP MISP
Classification
References
Sources
- CVE List CVE-2026-103239
- NVD CVE-2026-103239
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