THREATPORT/VULNERABILITY/CVE-2019-12519
CRITICAL SEVERITY

CVE-2019-12519

Squid vulnerability

CVSS
9.8
EPSS
6.7%
EPSS pct
93th
Exploited
No known
An issue was discovered in Squid through 4.7. When handling the tag esi:when when ESI is enabled, Squid calls ESIExpression::Evaluate. This function uses a fixed stack buffer to hold the expression while it's being evaluated. When processing the expression, it could either evaluate the top of the stack, or add a new member to the stack. When adding a new member, there is no check to ensure that the stack won't overflow.
Affected vendor
Squid Cache
Affected product
Squid
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Weakness type (CWE)
Published
2020-04-15

Risk analysis

Based on its CVSS vector, this vulnerability is exploitable over the network, low attack complexity, requiring no privileges, no user interaction. Successful exploitation leads to high impact to confidentiality, high impact to integrity, high impact to availability.

Its EPSS score of 6.7% reflects a lower probability of exploitation activity in the wild over the next 30 days, placing it above 93% of all scored CVEs.

Check your external exposure to CVE-2019-12519

  • Confirm whether Squid Cache Squid is running on any internet-facing host or subdomain.
  • Match discovered service fingerprints against the version affected by CVE-2019-12519.
  • Prioritise remediation if the asset is public, business-critical, or near authentication/payment flows.

How ThreatPort helps with CVE-2019-12519

ThreatPort's external attack surface scanner checks your internet-facing assets — agentlessly, from the outside in — for the exposed services and versions that CVE-2019-12519 affects, then prioritises the finding by real risk using CISA KEV and FIRST.org EPSS.

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Are you exposed to CVE-2019-12519?

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