CVE-2026-54345
Fix: gopacket/gopacket@145859dCVE-2026-54345 is a CWE-191 vulnerability in github.com/gopacket/gopacket. O3 Security confirms whether CVE-2026-54345 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
GoPacket's Diameter AVP decoder: uint32 underflow on vendor header size leads to unbounded ~4 GiB allocation (unauthenticated remote DoS)
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-2026-54345.
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/gopacket/gopacketReal-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
gopacket provides packet processing capabilities for Go. In version 1.6.0 and earlier, the Diameter AVP decoder computes an AVP data length by subtracting a fixed header size from an attacker-controlled AVP Length field, so a vendor-flagged AVP whose Length is smaller than the 12-byte header underflows the unsigned 32-bit value and drives an unbounded allocation of roughly 4 GiB, and two such messages in succession OOM-kill a collector, causing an unauthenticated remote denial of service. This issue is fixed in version 1.6.1.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/gopacket/gopacket | all versions | 1.6.1 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/gopacket/gopacket. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update github.com/gopacket/gopacket to 1.6.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-54345 is resolved across your whole dependency graph.
Workarounds
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 pinpoints whether CVE-2026-54345 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2026-54345. 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-2026-54345 in your dependencies?
O3 detects CVE-2026-54345 across Go dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.