CVE-2026-81820 (GCVE-0-2026-81820)

Vulnerability from cvelistv5 – Published: 2026-08-27 13:25 – Updated: 2026-08-27 19:39
VLAI
Title
Flowintel HTML Injection in MISP Case History Timeline via Crafted Object Attributes
Summary
Affected versions of Flowintel construct timeline HTML using attacker-controllable MISP object fields such as: * object UUID; * object name; * attribute value; * attribute type; * comment; * first/last seen values; * IDS flag. Those values were concatenated directly into HTML strings before rendering. The upstream commit explicitly states that DOMPurify removed XSS vectors but still allowed other HTML elements, such as forms, through. The fix replaces direct string interpolation with DOM construction via document.createElement() and assigns all attacker-controlled values using textContent. The headline is similarly converted to escaped HTML through a temporary element. Version impacted =>3.3.0
Severity
5.1 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-27 19:39 UTC
CWE
  • CWE-79 - Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting')
Assigner
References
Impacted products
Vendor Product Version CPE status
flowintel flowintel Affected: 0 , ≤ 3.3.0 (semver)
guessed Create a notification for this product.
Credits
Jeroen Pinoy David Cruciani
Show details on NVD website
To clipboard 

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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.