CVE-2017-12425

high-risk
Published 2017-08-04

An issue was discovered in Varnish HTTP Cache 4.0.1 through 4.0.4, 4.1.0 through 4.1.7, 5.0.0, and 5.1.0 through 5.1.2. A wrong if statement in the varnishd source code means that particular invalid requests from the client can trigger an assert, related to an Integer Overflow. This causes the varnishd worker process to abort and restart, losing the cached contents in the process. An attacker can therefore crash the varnishd worker process on demand and effectively keep it from serving content - a Denial-of-Service attack. The specific source-code filename containing the incorrect statement varies across releases.

Do I need to act?

~
1.0% chance of exploitation in next 30 days
EPSS score — moderate exploit probability
-
Not on CISA KEV list
No confirmed active exploitation reported to CISA
?
Patch status unknown
Check vendor advisories for fix availability and mitigation guidance
7
CVSS 7.5/10 High
NETWORK / LOW complexity

Affected Products (20)

Varnish
Varnish Cache
Varnish
Varnish Cache
Varnish Cache
Varnish Cache
Varnish Cache
Varnish Cache
Varnish Cache
Varnish Cache
Varnish Cache
Varnish Cache
Varnish Cache
Varnish Cache
Varnish
Varnish
Varnish
Varnish
Varnish Cache
Varnish Cache
52
/ 100
high-risk
Severity 26/34 · High
Exploitability 3/34 · Minimal
Exposure 23/34 · High