CVE-2026-49864
XSS in wetty allows script execution and keystroke injection into browser SSH sessions.
Is CVE-2026-49864 being exploited?
Not confirmed. CVE-2026-49864 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-2026-49864?
CVE-2026-49864 is rated High with a CVSS score of 8.6. 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-2026-49864?
Yes. A fix has been recorded for CVE-2026-49864. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-49864 affect?
CVE-2026-49864 affects wetty < 3.0.4, browser-based SSH terminals using wetty, deployments bundling wetty. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-49864?
Upgrade wetty to >=3.0.4 immediately; restrict untrusted file downloads.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Stored XSS via file-download causes script execution in wetty origin and injects attacker keystrokes into victim SSH, enabling command execution/session hijack.
Immediate action required
- affected< 3.0.4
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.