CVE-2019-17191

Exp

The Signal Private Messenger application before 4.47.7 for Android allows a caller to force a call to be answered, without callee user interaction, via a connect message. The existence of the call is noticeable to the callee; however, the audio channel may be open before the callee can block eavesdropping.

Published: 2019-10-05 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2019-17191 is rated High Exploit Risk (73/100): CVSS High severity, with medium exploitation likelihood (EPSS 1.80%). 2 public exploit reference(s) are indexed (Exploit-DB). EPSS rose +1.49% 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-2019-17191

EDB-ID Source Kind Published Link
— nvd_ref exploit_tag Exploit-DB ↗
— nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2019-17191

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 0.32% 1.80% +1.49%
2 2025-03-30 0.62% 0.32% -0.30%
3 2025-03-29 — 0.62% —

Full EPSS history (13 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2019-17191

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N 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:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
 3.9 3.6 [email protected]
5.0 2.0 MEDIUM
AV:N/AC:L/Au:N/C:P/I:N/A:N 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:N)
No integrity impact.
Availability impact (A:N)
No availability impact.
 10.0 2.9 [email protected]

Weakness enumeration for CVE-2019-17191

Affected software / configurations for CVE-2019-17191

Vendor Product Version Raw CPE
signal private_messenger < 4.47.7 cpe:2.3:a:signal:private_messenger:*:*:*:*:*:android:*:*

References for CVE-2019-17191

URL Tags
https://bugs.chromium.org/p/project-zero/issues/detail?id=1943 Exploit Third Party Advisory
https://news.ycombinator.com/item?id=21161432 Exploit Issue Tracking Third Party Advisory
https://twitter.com/moxie/status/1180261210341511168 Third Party Advisory
cvelogic Threat Intelligence