CVE-2026-35469
CVE-2026-35469 is a security vulnerability in github.com/moby/spdystream. O3 Security confirms whether CVE-2026-35469 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
SpdyStream: DOS on CRI
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.
Blast Radius
github.com/moby/spdystreamReal-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
spdystream is a Go library for multiplexing streams over SPDY connections. In versions 0.5.0 and below, the SPDY/3 frame parser does not validate attacker-controlled counts and lengths before allocating memory. Three allocation paths are affected: the SETTINGS frame entry count, the header count in parseHeaderValueBlock, and individual header field sizes — all read as 32-bit integers and used directly as allocation sizes with no bounds checking. Because SPDY header blocks are zlib-compressed, a small on-the-wire payload can decompress into large attacker-controlled values. A remote peer that can send SPDY frames to a service using spdystream can exhaust process memory and cause an out-of-memory crash with a single crafted control frame. This issue has been fixed in version 0.5.1.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/moby/spdystream | all versions | 0.5.1 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/moby/spdystream. 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/moby/spdystream to 0.5.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-35469 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-2026-35469 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-2026-35469. 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-2026-35469 in your dependencies?
O3 detects CVE-2026-35469 across Go dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.