CVE-2019-11705

CRITICAL

Thunderbird <60.7.1 - Buffer Overflow

Title source: llm
STIX 2.1

Exploitation Summary

EIP tracks 1 public exploit for CVE-2019-11705. PoCs published by X41 D-Sec GmbH.

AI-analyzed exploit summary The advisory describes a stack-based buffer overflow in Thunderbird's libical implementation (CVE-2019-11705), triggered by a malformed calendar attachment. The issue arises from missing sanity checks in `icalrecur_add_bydayrules()`, leading to an out-of-bounds write in a stack-allocated buffer.

Description

A flaw in Thunderbird's implementation of iCal causes a stack buffer overflow in icalrecur_add_bydayrules when processing certain email messages, resulting in a potentially exploitable crash. This vulnerability affects Thunderbird < 60.7.1.

Exploits (1)

exploitdb WRITEUP
by X41 D-Sec GmbH · textdosmultiple
https://www.exploit-db.com/exploits/47004

The advisory describes a stack-based buffer overflow in Thunderbird's libical implementation (CVE-2019-11705), triggered by a malformed calendar attachment. The issue arises from missing sanity checks in `icalrecur_add_bydayrules()`, leading to an out-of-bounds write in a stack-allocated buffer.

Classification
Writeup 100%
Attack Type
Rce
Complexity
Moderate
Reliability
Theoretical
Target: Thunderbird (all versions before ESR 60.7.XXX)
No auth needed
Prerequisites: Attacker must send a specially crafted calendar attachment to the victim
devstral-2 · analyzed Feb 16, 2026 Full analysis →

References (3)

Core 3
Core References
Issue Tracking, Permissions Required, Vendor Advisory x_refsource_misc
https://bugzilla.mozilla.org/show_bug.cgi?id=1553808
Third Party Advisory vendor-advisory x_refsource_gentoo
https://security.gentoo.org/glsa/201908-20

Scores

CVSS v3 9.8
EPSS 0.0990
EPSS Percentile 95.0%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Details

CWE
CWE-787
Status published
Products (1)
mozilla/thunderbird < 60.7.1
Published Jul 23, 2019
Tracked Since Feb 18, 2026