Vulnerability in Signal

CVE-2022-28345

The Signal app before 5.34 for iOS allows URI spoofing via RTLO injection. It incorrectly renders RTLO encoded URLs beginning with a non-breaking space, when there is a hash character in the URL. This technique allows a remote unauthenticated attacker to send legitimate looking links, appearing to be any website URL, by abusing the non-http/non-https automatic rendering of URLs. An attacker can spoof, for example, example.com, and masquerade any URL with a malicious destination. An attacker requires a subdomain such as gepj, txt, fdp, or xcod, which would appear backwards as jpeg, txt, pdf, and docx respectively.

EPSS: 0.022 (80.6th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2022-28345?
CVE-2022-28345 is a high-severity vulnerability in Signal, classified under Improper Neutralization of Special Elements in Output Used by a Downstream Component (Injection). CVSS score: 7.5/10. Published 2022-04-15.
How severe is CVE-2022-28345?
High severity. CVSS v3 base score is 7.5 out of 10.