Widely-used JS slider library; prototype pollution enables RCE; affects many apps.
CVE-2026-27212
Prototype pollution in Swiper JS (6.5.1–12.1.1) enables auth bypass, DoS, and RCE.
Is CVE-2026-27212 being exploited?
Not confirmed. CVE-2026-27212 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 0.40% probability of exploitation in the next 30 days.
How severe is CVE-2026-27212?
CVE-2026-27212 is rated Critical with a CVSS score of 9.4. 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-2026-27212?
Yes. A fix has been recorded for CVE-2026-27212. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-27212 affect?
CVE-2026-27212 affects Swiper JS library (versions 6.5.1–12.1.1). Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-27212?
Upgrade to 12.1.2+ immediately
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Pollutes Object.prototype via crafted input; attackers can bypass auth, trigger DoS, and execute code.
Immediate action required
- affected>= 6.5.1 and < 12.1.2
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.