CVE-2026-12221 (GCVE-0-2026-12221)

Vulnerability from cvelistv5 – Published: 2026-06-15 05:00 – Updated: 2026-06-15 05:00
VLAI
Title
Yealink SIP-T46U Firmware Chunk Upload upgrade sprintf stack-based overflow
Summary
A vulnerability was found in Yealink SIP-T46U 108.86.0.118. This impacts the function sprintf of the file /api/upgrade/upgrade of the component Firmware Chunk Upload Handler. Performing a manipulation of the argument uid/start_offset results in stack-based buffer overflow. The attack needs to be approached within the local network. The exploit has been made public and could be used. The vendor was contacted early about this disclosure but did not respond in any way.
Severity
8.6 (High)
CVSS:4.0/AV:A/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P
8 (High)
CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:P/RL:X/RC:R
8 (High)
CVSS:3.0/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:P/RL:X/RC:R
CWE
Assigner
References
URL Tags
https://vuldb.com/vuln/370864 vdb-entrytechnical-description
https://vuldb.com/vuln/370864/cti signaturepermissions-required
https://vuldb.com/cve/CVE-2026-12221 third-party-advisory
https://vuldb.com/submit/834207 third-party-advisory
http://cdn2.v50to.cc/T46U/T46U_mod_upgrade_Upgrad… broken-linkexploitpatch
Impacted products
Vendor Product Version
Yealink SIP-T46U Affected: 108.86.0.118
    cpe:2.3:a:yealink:sip-t46u:*:*:*:*:*:*:*:*
 Create a notification for this product.
Credits
CookedMelon (VulDB User) VulDB CNA Team
Show details on NVD website
To clipboard 

{
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      "affected": [
        {
          "cpes": [
            "cpe:2.3:a:yealink:sip-t46u:*:*:*:*:*:*:*:*"
          ],
          "modules": [
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          ],
          "product": "SIP-T46U",
          "vendor": "Yealink",
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        }
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          "tags": [
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    "dateReserved": "2026-06-14T13:54:18.805Z",
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    "state": "PUBLISHED"
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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

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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.