CVE-2019-11705
published 2019-07-23CVE-2019-11705: A flaw in Thunderbird's implementation of iCal causes a stack buffer overflow in icalrecur_add_bydayrules when processing certain email messages, resulting in…
PriorityP261critical9.8CVSS 3.1
AVNACLPRNUINSUCHIHAH
EXPLOIT
EPSS
9.90%
95.0th percentile
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.
Affected
7 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | thunderbird | < thunderbird 1:60.7.1-1 (bookworm) | thunderbird 1:60.7.1-1 (bookworm) |
| mozilla | thunderbird | < 60.7.1 | 60.7.1 |
| mozilla | thunderbird | >= 0 < 1:60.7.1-1 | 1:60.7.1-1 |
| mozilla | thunderbird | >= 0 < 1:60.7.1-1 | 1:60.7.1-1 |
| mozilla | thunderbird | >= 0 < 1:60.7.1-1 | 1:60.7.1-1 |
| mozilla | thunderbird | >= 0 < 1:60.7.1-1 | 1:60.7.1-1 |
| mozilla | thunderbird | >= unspecified < 60.7.1 | 60.7.1 |
Detection & IOCsextracted from sources · hover to see the quote
- →Trigger function is icalrecur_add_bydayrules() in icalrecur.c — monitor crashes or stack-smashing signals originating from this function when Thunderbird processes incoming email with iCal attachments. ↗
- →The overflow occurs when the BYDAY rule's weekno field takes an invalid (e.g. negative) value, causing an out-of-bounds write to a stack-allocated short array — look for malformed RRULE:BYDAY components in iCal data within email messages. ↗
- →Vulnerable Thunderbird versions are strictly below 60.7.1 — flag any Thunderbird process older than 60.7.1 processing iCal email as high-risk. ↗
- →libical versions prior to the commit 5b99f67f6 (pre v2.0.0, 2015-09-04) lack the negative-weekno guard and are vulnerable — audit libical version in use alongside Thunderbird. ↗
- ·Setting calendar.icaljs = true in Thunderbird preferences switches iCal parsing from the vulnerable libical to the JavaScript implementation (icaljs), mitigating the vulnerability without patching. ↗
- ·Red Hat Enterprise Linux 7 and 8 ship a libical version that already contains the negative-weekno fix and are listed as Not Affected; only RHEL 6 (out of support scope) required patching. ↗
CVSS provenance
nvdv3.19.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
nvdv2.07.5HIGHAV:N/AC:L/Au:N/C:P/I:P/A:P
osv9.8CRITICAL
vendor_debian9.8CRITICAL
vendor_redhat9.8CRITICAL
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Ubuntu
Thunderbird vulnerabilities
vendor_ubuntu·2019-06-20
CVE-2019-11703 Thunderbird vulnerabilities
Title: Thunderbird vulnerabilities
Summary: Several security issues were fixed in Thunderbird.
Multiple memory safety issues were discovered in Thunderbird. If a user
were tricked in to opening a specially crafted message, an attacker could
potentially exploit these to cause a denial of service, or execute
arbitrary code.
Instructions: After a standard system update you need to restart Thunderbird to make
all the necessary changes.
Red Hat
libical: Stack buffer overflow in icalrecur_add_bydayrules in icalrecur.c
vendor_redhat·2019-06-13·CVSS 9.8
CVE-2019-11705 [CRITICAL] CWE-121 libical: Stack buffer overflow in icalrecur_add_bydayrules in icalrecur.c
libical: Stack buffer overflow in icalrecur_add_bydayrules in icalrecur.c
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.
Mitigation: Thunderbird can be configured to use icaljs instead of libical by setting `calendar.icaljs = true` in preferences, mitigating this vulnerability.
Package: libical (Red Hat Enterprise Linux 6) - Out of support scope
Package: libical (Red Hat Enterprise Linux 7) - Not affected
Package: libical (Red Hat Enterprise Linux 8) - Not affected
Debian
CVE-2019-11705: thunderbird - A flaw in Thunderbird's implementation of iCal causes a stack buffer overflow in...
vendor_debian·2019·CVSS 9.8
CVE-2019-11705 [CRITICAL] CVE-2019-11705: thunderbird - A flaw in Thunderbird's implementation of iCal causes a stack buffer overflow in...
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.
Scope: local
bookworm: resolved (fixed in 1:60.7.1-1)
bullseye: resolved (fixed in 1:60.7.1-1)
forky: resolved (fixed in 1:60.7.1-1)
sid: resolved (fixed in 1:60.7.1-1)
trixie: resolved (fixed in 1:60.7.1-1)
GHSA
GHSA-jqv2-fc88-9266: A flaw in Thunderbird's implementation of iCal causes a stack buffer overflow in icalrecur_add_bydayrules when processing certain email messages, resu
ghsa_unreviewed·2022-05-24
CVE-2019-11705 [CRITICAL] CWE-787 GHSA-jqv2-fc88-9266: A flaw in Thunderbird's implementation of iCal causes a stack buffer overflow in icalrecur_add_bydayrules when processing certain email messages, resu
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.
OSV
CVE-2019-11705: A flaw in Thunderbird's implementation of iCal causes a stack buffer overflow in icalrecur_add_bydayrules when processing certain email messages, resu
osv·2019-07-23·CVSS 9.8
CVE-2019-11705 [CRITICAL] CVE-2019-11705: A flaw in Thunderbird's implementation of iCal causes a stack buffer overflow in icalrecur_add_bydayrules when processing certain email messages, resu
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.
No detection rules found.
Bugzilla
CVE-2019-11705 thunderbird: Stack buffer overflow in icalrecur_add_bydayrules in icalrecur.c [fedora-all]
bugzilla·2019-06-14·CVSS 9.8
CVE-2019-11705 [CRITICAL] CVE-2019-11705 thunderbird: Stack buffer overflow in icalrecur_add_bydayrules in icalrecur.c [fedora-all]
CVE-2019-11705 thunderbird: Stack buffer overflow in icalrecur_add_bydayrules in icalrecur.c [fedora-all]
This is an automatically created tracking bug! It was created to ensure
that one or more security vulnerabilities are fixed in affected versions
of fedora-all.
For comments that are specific to the vulnerability please use bugs filed
against the "Security Response" product referenced in the "Blocks" field.
For more information see:
http://fedoraproject.org/wiki/Security/TrackingBugs
When submitting as an update, use the fedpkg template provided in the next
comment(s). This will include the bug IDs of this tracking bug as well as
the relevant top-level CVE bugs.
Please also mention the CVE IDs being fixed in the RPM changelog and the
fedpkg commit message.
NOTE: this issue affects
Bugzilla
CVE-2019-11705 libical: Stack buffer overflow in icalrecur_add_bydayrules in icalrecur.c
bugzilla·2019-06-12·CVSS 9.8
CVE-2019-11705 [CRITICAL] CVE-2019-11705 libical: Stack buffer overflow in icalrecur_add_bydayrules in icalrecur.c
CVE-2019-11705 libical: Stack buffer overflow in icalrecur_add_bydayrules in icalrecur.c
A flaw was found in Mozilla Thunderbird. A stack-based buffer overflow in in icalrecur_add_bydayrules in icalrecur.c leads to server crash and potentially worse consequences.
References:
https://bugzilla.mozilla.org/show_bug.cgi?id=1553808
Discussion:
Is this for Thunderbird only, or the libical package is also affected? I would verify that myself, but I do not have access to any related bug report mentioned here, neither to the upstream Mozilla bug.
---
External References:
https://www.mozilla.org/en-US/security/advisories/mfsa2019-17/
---
Mitigation:
Thunderbird can be configured to use icaljs instead of libical by setting `calendar.icaljs = true` in preferences, mitigating this vulnerabil
https://bugzilla.mozilla.org/show_bug.cgi?id=1553808https://security.gentoo.org/glsa/201908-20https://www.mozilla.org/security/advisories/mfsa2019-17/https://bugzilla.mozilla.org/show_bug.cgi?id=1553808https://security.gentoo.org/glsa/201908-20https://www.mozilla.org/security/advisories/mfsa2019-17/
2019-07-23
Published