CVE-2026-59803
Unauthenticated gzip decompression leads to OOM DoS in rpcx
Is CVE-2026-59803 being exploited?
Not confirmed. CVE-2026-59803 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 0.74% probability of exploitation in the next 30 days.
How severe is CVE-2026-59803?
CVE-2026-59803 is rated High. 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-2026-59803?
Yes. A fix has been recorded for CVE-2026-59803. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-59803 affect?
CVE-2026-59803 affects rpcx <= 1.9.3, Go services using rpcx protocol.Message.Decode. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-59803?
Upgrade to commit 047aec1 / fixed release; disable compression and apply input size limits
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Unauthenticated remote DoS: crafted gzip-compressed message expands to gigabytes during decode, causing OOM and service outage.
Immediate action required
- affected<= 1.9.3
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.