CVE-2026-29781 — sliver
CVE-2026-29781 is a NULL Pointer Dereference vulnerability in github.com/bishopfox/sliver. 1 public exploit reference exists, so weaponization risk is real. No vendor fix is recorded yet; mitigation options are listed below.
Sliver: Authenticated Nil-Pointer Dereference in Handlers
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.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-29781.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
Real-World Exposure
github.com/bishopfox/sliverReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
Description
Sliver is a command and control framework that uses a custom Wireguard netstack. In versions from 1.7.3 and prior, a vulnerability exists in the Sliver C2 server's Protobuf unmarshalling logic due to a systemic lack of nil-pointer validation. By extracting valid implant credentials and omitting nested fields in a signed message, an authenticated actor can trigger an unhandled runtime panic. Because the mTLS, WireGuard, and DNS transport layers lack the panic recovery middleware present in the HTTP transport, this results in a global process termination. While requiring post-authentication access (a captured implant), this flaw effectively acts as an infrastructure "kill-switch," instantly severing all active sessions across the entire fleet and requiring a manual server restart to restore operations. At time of publication, there are no publicly available patches.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/bishopfox/sliver | all versions | No fix |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/bishopfox/sliver, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Remediation status
No patched version of github.com/bishopfox/sliver has shipped for CVE-2026-29781 yet. Where your build allows, override or pin the dependency away from the vulnerable range, and apply any maintainer-recommended mitigation.
Mitigate without a patch
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2026-29781 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2026-29781. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-29781 in your dependencies?
O3 Security finds CVE-2026-29781 across Go dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.