CVE-2026-14899 (GCVE-0-2026-14899)

Vulnerability from cvelistv5 – Published: 2026-07-22 19:19 – Updated: 2026-07-22 19:19
VLAI
Title
Off-by-one out of bounds read in MIME header parser for forwarding
Summary
The code to parse MIME headers for display when forwarding a message (if the setting to view all headers was enabled) had an off-by-one error, allowing a single byte to be read from the memory after the buffer for the headers, and potentially crashing Thunderbird. This vulnerability was fixed in Thunderbird 153 and Thunderbird 140.13.
Severity
No CVSS data available.
Assigner
References
Impacted products
Vendor Product Version
Mozilla Thunderbird Unaffected: 140.13 , ≤ 140.* (rpm)
Unaffected: 153 , ≤ * (rpm)
Create a notification for this product.
Credits
Claude, Kai Engert
Show details on NVD website
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              "versionType": "rpm"
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        }
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      "providerMetadata": {
        "dateUpdated": "2026-07-22T19:19:42.305Z",
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        "shortName": "mozilla"
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    "cveId": "CVE-2026-14899",
    "datePublished": "2026-07-22T19:19:42.305Z",
    "dateReserved": "2026-07-06T19:53:12.713Z",
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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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