CVE-2019-11703

Exp

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

Published: 2019-07-23 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2019-11703 is rated High Exploit Risk (89.9/100): CVSS Critical severity, with high exploitation likelihood (EPSS 10.53%, 95th percentile). 2 public exploit reference(s) are indexed (Exploit-DB). EPSS rose +2.37% over the last day, indicating growing attacker interest. Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2019-11703

EDB-ID Source Kind Published Link
47003 exploit_db edb 2019-06-17 Exploit-DB ↗
— nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2019-11703

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 8.15% 10.53% +2.37%
2 2026-05-08 8.30% 8.15% -0.14%
3 2025-11-21 — 8.30% —

Full EPSS history (23 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2019-11703

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
9.8 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 5.9 [email protected]
7.5 2.0 HIGH
AV:N/AC:L/Au:N/C:P/I:P/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
 10.0 6.4 [email protected]

Weakness enumeration for CVE-2019-11703

OS Trackers for CVE-2019-11703

vendor priority summary link
debian not yet assigned CVE-2019-11703 not yet assigned priority: Debian including 1 source packages (thunderbird), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2019-11703
gentoo normal CVE-2019-11703: 1 GLSA(s) (201908-20), 2 atom(s) (mail-client/thunderbird, mail-client/thunderbird-bin); latest impact normal. https://bugs.gentoo.org/buglist.cgi?quicksearch=CVE-2019-11703
redhat medium — https://access.redhat.com/security/cve/CVE-2019-11703
suse medium CVE-2019-11703 severity moderate: SUSE including 33 source package names (MozillaThunderbird-60.7.2-3.43.1, MozillaThunderbird-60.7.2-85.1, …), 50 product×package rows across 20 product lines (SUSE Liberty Linux 7, SUSE Liberty Linux 8, … (20 product lines)): Fixed 50. https://www.suse.com/security/cve/CVE-2019-11703/
ubuntu medium CVE-2019-11703 medium priority: Ubuntu including 1 source packages (thunderbird), 6 status rows across 6 suites (bionic, cosmic, disco, trusty, upstream, xenial): released 5, DNE 1. https://ubuntu.com/security/CVE-2019-11703

Affected software / configurations for CVE-2019-11703

Vendor Product Version Raw CPE
mozilla thunderbird < 60.7.1 cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*

References for CVE-2019-11703

cvelogic Threat Intelligence