Symfony is a widely used PHP framework; this XXE can expose local files from many web apps and affects many deployed sites — high-impact for web infrastructure.
CVE-2026-45071
Symfony XXE bug allows attacker-supplied XML to read local files via Crawler::addXmlContent().
Is CVE-2026-45071 being exploited?
Not confirmed. CVE-2026-45071 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.57% probability of exploitation in the next 30 days.
How severe is CVE-2026-45071?
CVE-2026-45071 is rated High with a CVSS score of 8.7. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-45071?
Yes. A fix has been recorded for CVE-2026-45071. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-45071 affect?
CVE-2026-45071 affects Symfony < 5.4.52, Symfony < 6.4.40, Symfony < 7.4.12, Symfony < 8.0.12, and 1 further product or version. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-45071?
Upgrade to 5.4.52/6.4.40/7.4.12/8.0.12 and block/validate untrusted XML input.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
XML External Entity (XXE) enables local file disclosure and possible SSRF/data exfiltration via crafted XML sent to the application.
Immediate action required
- affected< 5.4.52
- affected>= 6.0.0-BETA1 and < 6.4.40
- affected>= 7.0.0-BETA1 and < 7.4.12
- affected>= 8.0.0-BETA1 and < 8.0.12
- affected< 5.4.52
- affected>= 6.0.0-BETA1 and < 6.4.40
- affected>= 7.0.0-BETA1 and < 7.4.12
- affected>= 8.0.0-BETA1 and < 8.0.12
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.