CVE-2020-14058
NVD-CWE-noinfoPublished: June 30, 2020· Updated: Jun 17, 2026
Official Description
An issue was discovered in Squid before 4.12 and 5.x before 5.0.3. Due to use of a potentially dangerous function, Squid and the default certificate validation helper are vulnerable to a Denial of Service when opening a TLS connection to an attacker-controlled server for HTTPS. This occurs because unrecognized error values are mapped to NULL, but later code expects that each error value is mapped to a valid error string.
Technical Analysis
CVE-2020-14058 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.
The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.
A successful exploit results in availability disruption (denial of service), with a CVSS base score of 7.5.
CVSS v3.1 Vector Breakdown
Affected Vendors & Products
Exploit & PoC Resources
Official Patches & Advisories
All References (10)
Quick Facts
Related CVEs (NVD-CWE-noinfo)
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2020-14058 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts