CVE-2026-10722: Cilium eBPF Privilege Escalation Flaw

CVE-2026-10722 Overview

CVE-2026-10722 is an integer overflow vulnerability in the cilium/ebpf Go library through version 0.21.0. The flaw resides in the loadRawSpec function within btf/btf.go, part of the LoadCollectionSpec and LoadCollectionSpecFromReader code paths. Attackers can trigger the overflow by manipulating the offset argument when the library parses BPF Type Format (BTF) data. Exploitation requires local access and low privileges. The maintainers addressed the issue in commit 533dfc82fd228bfadf42ea7180c39de7d9af47fa.

Critical Impact
A local actor supplying a crafted eBPF object can cause integer overflow during BTF parsing, potentially leading to limited availability impact in applications that load untrusted eBPF programs.

Affected Products

cilium/ebpf Go library versions up to and including 0.21.0
Applications embedding LoadCollectionSpec or LoadCollectionSpecFromReader to parse BTF data
Downstream consumers of the btf package prior to the patched commit

Discovery Timeline

2026-06-03 - CVE-2026-10722 published to NVD
2026-06-03 - Last updated in NVD database

Technical Details for CVE-2026-10722

Vulnerability Analysis

The vulnerability is classified under [CWE-189] (Numeric Errors). It occurs in loadRawSpec, the routine responsible for deserializing raw BTF metadata from ELF sections or arbitrary readers. When the function processes a controlled offset value, arithmetic on that offset wraps around the bounds of the integer type. The wrapped value then participates in subsequent length or pointer calculations against the BTF buffer.

Because cilium/ebpf is the canonical Go library for loading eBPF programs, the parser is reachable from any process that ingests user-supplied BTF blobs. The issue is local-only because BTF data is loaded from files or in-memory readers controlled by a local context, not over the network.

Root Cause

The root cause is missing bounds validation on the offset argument before it is used in arithmetic inside loadRawSpec in btf/btf.go. The function trusts the supplied offset and combines it with section sizes without checking for wraparound. The upstream patch in commit 533dfc82fd228bfadf42ea7180c39de7d9af47fa adds the necessary validation to reject malformed offsets prior to use.

Attack Vector

A local attacker provides a crafted BTF blob or ELF object that is parsed by an application calling LoadCollectionSpec or LoadCollectionSpecFromReader. The malformed offset triggers integer overflow in loadRawSpec, producing inconsistent state during parsing. The vulnerability requires local access with low privileges and no user interaction. A public proof-of-concept has been published, increasing the likelihood of opportunistic abuse against tools that consume untrusted eBPF artifacts.

No verified exploit code is reproduced here. Technical details are available in the cilium/ebpf issue tracker and the corresponding pull request.

Detection Methods for CVE-2026-10722

Indicators of Compromise

Unexpected crashes or panics in Go binaries that import github.com/cilium/ebpf when loading BPF objects
Presence of unsigned or untrusted .o BPF object files in directories consumed by privileged loaders
Process invocations passing attacker-writable paths to applications that call LoadCollectionSpec

Detection Strategies

Inventory all Go binaries linked against cilium/ebpf at version 0.21.0 or earlier using software composition analysis
Audit code paths that pass untrusted file or reader input into LoadCollectionSpec and LoadCollectionSpecFromReader
Monitor for abnormal termination signals or panics emitted by eBPF-loading services in container runtimes and observability agents

Monitoring Recommendations

Enable host telemetry on bpf() syscalls and on file reads of .btf and .o artifacts by privileged loaders
Alert when non-root users write BPF object files to locations later consumed by privileged processes
Track upstream advisories on the cilium/ebpf repository for related parser fixes

How to Mitigate CVE-2026-10722

Immediate Actions Required

Upgrade the cilium/ebpf dependency to a version that includes commit 533dfc82fd228bfadf42ea7180c39de7d9af47fa
Rebuild and redeploy all Go binaries that statically link against the affected library
Restrict which local accounts can supply BTF or BPF object input to privileged loaders

Patch Information

The fix is committed upstream as 533dfc82fd228bfadf42ea7180c39de7d9af47fa in the cilium/ebpf repository. The patch adds offset validation in loadRawSpec to prevent integer overflow during BTF parsing. Consumers should bump their go.mod entry past version 0.21.0 to a release that includes this commit and re-run go mod tidy and go build.

Workarounds

Refuse to load BPF objects from filesystem paths writable by non-privileged users until the library is upgraded
Apply filesystem permissions and mandatory access controls to restrict who can place .o or .btf files in loader-consumed directories
Validate BTF section sizes and offsets in calling code before invoking LoadCollectionSpec or LoadCollectionSpecFromReader

bash

# Update the cilium/ebpf dependency in a Go module
go get github.com/cilium/ebpf@latest
go mod tidy
go build ./...