cve.bz

CVE-2019-12519

9.8 criticalEPSS 6.7%

Critical (9.8). EPSS 6.7% chance of exploitation in the next 30 days.

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.

Severity

CVSS 3.1

9.8 critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS
6.7% chance of exploitation in the next 30 days; higher than 93% of CVEs (scores of 2026-10-31)
CWE
CWE-787
Published
Modified
Record from
the NVD, synced

Affected

References

Check your stackJSON