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CVE-2026-90556 (GCVE-0-2026-90556)

Vulnerability from cvelistv5 – Published: 2026-09-12 18:06 – Updated: 2026-09-12 18:06
VLAI
Title
Freeciv before 3.2.6 Heap Buffer Overflow via worklist_load
Summary
Freeciv versions before 3.2.6 contain a heap buffer overflow in worklist_load() when processing savegame files with declared worklist lengths exceeding the fixed array bound of 64 elements. Attackers can craft malicious savegame files that write past the entries array into adjacent heap-allocated struct fields, potentially corrupting memory when a user or server operator loads the file.
Severity
8.5 (High)
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
CWE
  • CWE-122 - Heap-based Buffer Overflow
Assigner
References
Impacted products
Vendor Product Version CPE status
freeciv freeciv Affected: 0 , < 3.2.6 (semver)
    cpe:2.3:a:freeciv:freeciv:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-08-23 00:00
Credits
Tristan Madani
Show details on NVD website
To clipboard 

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          "repo": "https://github.com/freeciv/freeciv",
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      ],
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          "url": "https://github.com/freeciv/freeciv/blob/R3_2_5/server/savegame/savegame3.c#L964"
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          "url": "https://github.com/freeciv/freeciv/blob/R3_2_5/server/savegame/savegame2.c#L788"
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    "assignerShortName": "VulnCheck",
    "cveId": "CVE-2026-90556",
    "datePublished": "2026-09-12T18:06:41.013Z",
    "dateReserved": "2026-09-12T11:13:43.326Z",
    "dateUpdated": "2026-09-12T18:06:41.013Z",
    "state": "PUBLISHED"
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    "redhat_vex": {
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      "cve": "CVE-2026-90556",
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}



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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.


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