CVE-2026-103500
published 2026-09-30CVE-2026-103500: An attacker could cause a heap buffer overflow by getting a user to open an email that is greater than or equal to 2GB in size. This vulnerability was fixed in…
PriorityP424medium6.1CVSS 3.1
AVLACLPRNUIRSUCNILAH
EPSS
0.21%
11.1th percentile
An attacker could cause a heap buffer overflow by getting a user to open an email that is greater than or equal to 2GB in size. This vulnerability was fixed in Thunderbird 157, Thunderbird 140.17, and Thunderbird 153.4.
Affected
7 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| mozilla | thunderbird | < Thunderbird 140.17 | Thunderbird 140.17 |
| mozilla | thunderbird | < Thunderbird 157 | Thunderbird 157 |
| mozilla | thunderbird | < Thunderbird 153.4 | Thunderbird 153.4 |
| mozilla | thunderbird | < 140.17.0 | 140.17.0 |
| mozilla | thunderbird | — | — |
| mozilla | thunderbird | >= 141.0 < 153.4.0 | 153.4.0 |
| mozilla | thunderbird | >= 154.0 < 157.0 | 157.0 |
CVSS provenance
nvdv3.16.1MEDIUMCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H
vendor_redhat8.8HIGH
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Red Hat
thunderbird: thunderbird: Heap buffer overflow via opening large emails
vendor_redhat·2026-09-30·CVSS 8.8
CVE-2026-103500 [HIGH] CWE-787 thunderbird: thunderbird: Heap buffer overflow via opening large emails
thunderbird: thunderbird: Heap buffer overflow via opening large emails
A flaw was found in Thunderbird. A remote attacker could exploit this vulnerability by convincing a user to open an email that is 2GB or larger, triggering a heap buffer overflow. This flaw allows an attacker to corrupt memory, which may cause an application crash, resulting in a Denial of Service (DoS), or potentially lead to arbitrary code execution.
Package: thunderbird (Red Hat Enterprise Linux 10) - Affected
Package: thunderbird (Red Hat Enterprise Linux 8) - Affected
Package: thunderbird (Red Hat Enterprise Linux 9) - Affected
Mozilla
Mozilla Foundation Security Advisory 2026-102: CVE-2026-103500
vendor_mozilla
CVE-2026-103500 Mozilla Foundation Security Advisory 2026-102: CVE-2026-103500
Mozilla Foundation Security Advisory 2026-102
CVE: CVE-2026-103500
Product: Thunderbird
Impact: moderate
Fixed in: Thunderbird 140.17
Mozilla
Mozilla Foundation Security Advisory 2026-101: CVE-2026-103500
vendor_mozilla
CVE-2026-103500 Mozilla Foundation Security Advisory 2026-101: CVE-2026-103500
Mozilla Foundation Security Advisory 2026-101
CVE: CVE-2026-103500
Product: Thunderbird
Impact: low
Fixed in: Thunderbird 157
Mozilla
Mozilla Foundation Security Advisory 2026-103: CVE-2026-103500
vendor_mozilla
CVE-2026-103500 Mozilla Foundation Security Advisory 2026-103: CVE-2026-103500
Mozilla Foundation Security Advisory 2026-103
CVE: CVE-2026-103500
Product: Thunderbird
Impact: low
Fixed in: Thunderbird 153.4
GHSA
An attacker could cause a heap buffer overflow by getting a user to open an email that is greater than or equal to 2GB in size.
ghsa_unreviewed·2026-09-30
CVE-2026-103500 An attacker could cause a heap buffer overflow by getting a user to open an email that is greater than or equal to 2GB in size.
An attacker could cause a heap buffer overflow by getting a user to open an email that is greater than or equal to 2GB in size. This vulnerability was fixed in Thunderbird 157, Thunderbird 140.17, and Thunderbird 153.4.
No detection rules found.
No public exploits indexed.
2026-09-30
Published