FFmpeg is a widely used multimedia library; a remote heap overflow in the RIST reader can enable code execution across many apps and streaming servers.
CVE-2026-75143
Heap overflow in FFmpeg RIST reader allows remote code execution via async:rist URL
Is CVE-2026-75143 being exploited?
Not confirmed. CVE-2026-75143 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-2026-75143?
CVE-2026-75143 is rated Critical with a CVSS score of 9.3. 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-2026-75143?
Yes. A fix has been recorded for CVE-2026-75143. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-75143 affect?
CVE-2026-75143 affects FFmpeg (libavformat/librist.c), Applications embedding FFmpeg, Media/streaming servers using RIST/async:rist URLs, Devices appliances embedding FFmpeg. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-75143?
Upgrade FFmpeg to commit 1c10bcc or later; block/disable RIST inputs until patched
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Remote attacker can send crafted RIST packets to overflow caller buffers, causing crashes or arbitrary code execution in processes using FFmpeg.
Immediate action required
- affected< 1c10bcc2e17255dacb717a25ab3db142ce390602
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.