CVE-2026-109619: Fatal-error backtrace use-after-free and OPcache type confusion

critical KEV Affects PHP engine. Feed 2026.10.29.1, updated 2026-10-28; published 2026-10-21; listed on CISA KEV 2026-10-26.

Fatal-error backtrace use-after-free and OPcache type confusion

Package: PHP engine PHP engine
Affected branches: 8.2 → fixed in 8.2.35; 8.3 → fixed in 8.3.36; 8.4 → fixed in 8.4.27; 8.5 → fixed in 8.5.12
Severity: critical CVSS 9.2
Exploitation: KEV listed by CISA as actively exploited · EPSS 100% (100.0th percentile)
Remediation: Upgrade to 8.5.12 / 8.4.27 / 8.3.36 / 8.2.35. 8.1 and older are end-of-life.
Published: 2026-10-21

References

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