CVE-2026-104433 — mooncake
Fix: kvcache-ai/Mooncake@c142b40CVE-2026-104433 is a Out-of-bounds Read vulnerability. A fix is available — see the affected versions and patch details below.
Mooncake before 0.3.12 Out-of-Bounds Read via P2P Handshake readString
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-104433.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
Description
Mooncake transfer engine before 0.3.12 contains an out-of-bounds read vulnerability in the readString function of include/common.h that allows unauthenticated attackers to crash the service by sending a zero-length handshake frame. Attackers can connect to the handshake port listening on all interfaces and send an eight-byte frame to terminate the hosting process, such as an SGLang inference server.
Detection & mitigation playbook
VulnerabilityDetect
Identify every host running the affected component and compare the installed build against the fixed version below — for source-built or distro-packaged software the version string, not a lockfile, is the source of truth (`dpkg -l`, `rpm -q`, or the binary's own `--version`).
Fix
Upgrade the affected component to the fixed release for CVE-2026-104433, or apply your distribution's backported patch — distro builds are often patched at an older version number, so check your vendor's advisory rather than the upstream version alone.
Workarounds
Constrain what reaches the vulnerable code: limit the size and shape of untrusted input, isolate the affected component in a sandboxed or least-privileged process, and enable the platform's memory-safety mitigations (ASLR, stack protector, hardened allocator) so an out-of-bounds access is more likely to fail closed than to be exploitable.
Frequently Asked Questions
Is CVE-2026-104433 in your dependencies?
Find it across , including transitive dependencies.