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CVE-2026-93872 (GCVE-0-2026-93872)

Vulnerability from cvelistv5 – Published: 2026-09-18 19:56 – Updated: 2026-09-18 19:56
VLAI
Title
Cotonti 1.0.0 PHP Object Injection via Comments Plugin Edit Action cb Parameter
Summary
Cotonti 1.0.0 passes the base64-decoded cb parameter to unserialize() without allowed_classes restriction in the comments plugin EditAction. Registered users with comment write permissions can instantiate arbitrary PHP objects and potentially achieve file write or code execution through gadget chains.
Severity
7.7 (High)
CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
7.5 (High)
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
CWE
  • CWE-502 - Deserialization of Untrusted Data
Assigner
References
Impacted products
Vendor Product Version CPE status
Cotonti Cotonti Affected: 1.0.0 , ≤ 1.0.0 (custom)
    cpe:2.3:a:cotonti:cotonti_siena:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-09-17 00:00
Credits
Harsh Raj Singhania
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

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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.


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