Thunderbird EUVD-2026-99207

| CVE-2026-110247

2026-10-13 mozilla

GHSA-6c5g-4xv7-7fmm

View

Awaiting Data No severity or threat signals available yet. Label will update when CVSS score is published or threat intelligence arrives. Why: No CVSS yet + weak signal (CWE or non-zero EPSS).

No patch listed yet 0.2% exploitation probability (EPSS)

Get an e-mail when this CVE is exploited, patched or re-scored. Free account.

Alert me

AnalysisCVE.org

Several buffer-growth sites in libmime performed size arithmetic in 32-bit types without overflow checks. On a sufficiently large message the growth guard could fail open, or the buffer could be reallocated smaller than required, and a subsequent memcpy would then write attacker-controlled data across adjacent heap allocations. This vulnerability was fixed in Thunderbird 158.

Affects your stack

Find out whether the stacks and servers you run are on an affected version.

Checking this CVE against your own stacks and servers is part of the Basic plan and up.

Know when Thunderbird gets its next vulnerability

Watch products and get an email when something new is published
Check this CVE against your own stack and servers
Exploit and PoC references, threat intelligence from 22 sources

Continue with Google Continue with GitHub

No credit card · 7-day full trial

Threat Intelligence Overview

EPSS Score

0.2%

Top 94% exploitable

Data Quality

1 sources

Confidence: Low

EUVD

CVE.org

EPSS

How this decision was reached

The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.

SignalValue

Severity Not scored yet

CISA KEV No

Public POC No

EPSS 0.2%

Patch available No

Active threat No

Deciding rule

No CVSS yet + weak signal (CWE or non-zero EPSS)

What every action level means

Emergency Immediate action required. Criteria: CRITICAL + in CISA KEV (actively exploited) without patch, OR CRITICAL + EPSS > 30% without patch, OR CRITICAL + active threat signals without patch.

Act Now Prioritize within 24-48h. Criteria: in KEV with patch available, OR CRITICAL + public POC, OR HIGH + EPSS > 10%, OR CRITICAL + active threat, OR any CRITICAL severity.

This Week Schedule remediation this week. Criteria: HIGH severity (CVSS 7.0-8.9). Patch within normal change window.

This Month Plan within 30 days. Criteria: MEDIUM severity (CVSS 4.0-6.9), lower exploitation probability. Include in regular patch cycle.

Monitor Track and reassess. Criteria: LOW severity (CVSS 0.1-3.9), minimal exploitation risk. No immediate action needed.

Attack Technique

Buffer Overflow HIGH

A buffer overflow occurs when a program writes more data to a memory buffer than it was allocated to hold, causing the excess data to spill into adjacent memory regions.

Affected Products (CPE)CVE.org

cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*

More in Thunderbird

View all

CVE-2013-1690 HIGH Act Now POC

8.8 Jun 26

Mozilla Firefox before 22.0, Firefox ESR 17.x before 17.0.7, Thunderbird before 17.0.7, and Thunderbird ESR 17.x before

CVE-2013-0758 CRITICAL Emergency POC

9.3 Jan 13

Mozilla Firefox before 18.0, Firefox ESR 10.x before 10.0.12 and 17.x before 17.0.2, Thunderbird before 17.0.2, Thunderb

CVE-2013-0753 CRITICAL Act Now POC

9.3 Jan 13

Use-after-free vulnerability in the serializeToStream implementation in the XMLSerializer component in Mozilla Firefox b

CVE-2012-3993 CRITICAL Emergency POC

9.3 Oct 10

The Chrome Object Wrapper (COW) implementation in Mozilla Firefox before 16.0, Firefox ESR 10.x before 10.0.8, Thunderbi

CVE-2013-1710 CRITICAL Emergency POC

10.0 Aug 07

The crypto.generateCRMFRequest function in Mozilla Firefox before 23.0, Firefox ESR 17.x before 17.0.8, Thunderbird befo

CVE-2013-0757 CRITICAL Emergency POC

9.3 Jan 13

The Chrome Object Wrapper (COW) implementation in Mozilla Firefox before 18.0, Firefox ESR 17.x before 17.0.2, Thunderbi

CVE-2014-1510 CRITICAL Emergency POC

9.8 Mar 19

The Web IDL implementation in Mozilla Firefox before 28.0, Firefox ESR 24.x before 24.4, Thunderbird before 24.4, and Se

CVE-2014-1511 CRITICAL Emergency POC

9.8 Mar 19

Mozilla Firefox before 28.0, Firefox ESR 24.x before 24.4, Thunderbird before 24.4, and SeaMonkey before 2.25 allow remo

CVE-2016-1960 HIGH Act Now POC

8.8 Mar 13

Integer underflow in the nsHtml5TreeBuilder class in the HTML5 string parser in Mozilla Firefox before 45.0 and Firefox

CVE-2024-9680 CRITICAL Act Now POC

9.8

Alpine Linux: mozjs fixed in 128.3.1-r0

CVE-2015-0816 MEDIUM This Month POC

5.0 Apr 01

Mozilla Firefox before 37.0, Firefox ESR 31.x before 31.6, and Thunderbird before 31.6 do not properly restrict resource

CVE-2013-2566 MEDIUM This Month POC

5.9 Mar 15

The RC4 algorithm, as used in the TLS protocol and SSL protocol, has many single-byte biases, which makes it easier for

Same technique Buffer Overflow

View all

CVE-2017-7269 CRITICAL POC

9.8

CVE-2015-5119 CRITICAL POC

9.8

CVE-2015-3113 CRITICAL POC

9.8

CVE-2011-2462 CRITICAL POC

9.8

CVE-2020-0796 CRITICAL POC

10.0

CVE-2019-11043 CRITICAL POC

9.8

CVE-2009-0927 HIGH POC

8.8

CVE-2012-1889 HIGH POC

8.8

References

Advisories & patches

ADVISORY https://nvd.nist.gov/vuln/detail/CVE-2026-110247 REF https://bugzilla.mozilla.org/show_bug.cgi?id=2071621 REF https://www.mozilla.org/security/advisories/mfsa2026-109/

Search Externally

GitHub PoC

Exploit-DB PacketStorm Snyk Rapid7 Nuclei Templates Trickest PoC

Back