How severe is CVE-2026-55883?

No CVSS score has been assigned to CVE-2026-55883 yet. Review the advisory details and affected package list to assess your exposure.

Which packages are affected by CVE-2026-55883?

CVE-2026-55883 affects the following packages: github.com/tilt-dev/tilt (Go). Ecosystems affected: Go.

How do I fix CVE-2026-55883?

Update github.com/tilt-dev/tilt to 0.37.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-55883 is resolved across your whole dependency graph.

How do I detect CVE-2026-55883 in my Go dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/tilt-dev/tilt, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2026-55883 if there is no patch (or I can't update yet)?

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.

Is CVE-2026-55883 actively exploited in the wild?

No public exploit code has been indexed for CVE-2026-55883 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2026-55883?

CVE-2026-55883 has an EPSS (Exploit Prediction Scoring System) score of 0.3%, placing it in the 17th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2026-55883?

CVE-2026-55883 is classified as CWE-345 (CWE-345). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2026-55883 published, and has it been updated?

CVE-2026-55883 was published on July 10, 2026 and was last updated on August 12, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🐹 Go

Not in CISA KEV

CVE-2026-55883 — tilt

Fix: tilt-dev/tilt@47393fb

CVE-2026-55883 is a CWE-345 vulnerability in github.com/tilt-dev/tilt. A fix is available for github.com/tilt-dev/tilt — see the affected versions and patch details below.

Tilt: Cross-site WebSocket hijacking of the Tilt HUD stream

Also known asGHSA-6m68-r693-78qxGO-2026-5181

Published

Jul 10, 2026

Updated

Aug 12, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

Exploitation data as of Oct 9, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

No confirmed exploitation observed yet

CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.

Exploitation and automatability from CISA’s SSVC triage for CVE-2026-55883.

EPSS Exploitation Probability

via FIRST.org ↗

0.3%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs17th percentile — riskier than 17% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

Real-World Exposure

1 pkg affected

🐹github.com/tilt-dev/tilt

Real-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

Summary

The Tilt HUD WebSocket (/ws/view) is gated by a CSRF token, but the token is served by an unauthenticated endpoint and the upgrader accepts any client that omits an Origin header. When the HUD is network-exposed, an attacker can open the HUD stream and read the developer's session state.

Details

The upgrader accepts a connection when the csrf query parameter matches a process-wide token (websocketCSRFToken). That token is served as text/plain by an unauthenticated handler (WebsocketToken, mounted at /api/websocket_token), so any reachable caller can fetch it and connect to /ws/view?csrf=<token>. When the parameter does not match, the upgrader falls back to a same-origin check that returns true when the Origin header is absent, so a non-browser client that omits Origin is accepted anyway. The token has no per-session binding.

Impact

An attacker who can reach the HUD listener can open the HUD WebSocket and receive the full view stream — session state, Tiltfile contents, resource statuses, and continued updates — defeating the intended anti-CSWSH protection.

Conditions for exploitation

Affected version in >= 0.24.0, <= 0.37.3.
HUD bound to a non-loopback address (tilt up --host 0.0.0.0, or TILT_HOST set).
Network reachability to the listener (default port 10350).

Not affected

The default loopback-only bind is not reachable from the network.

Workarounds

Use the default loopback bind (omit --host, unset TILT_HOST). No complete workaround short of upgrading for non-loopback deployments.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🐹Go	`github.com/tilt-dev/tilt`	≥ 0.24.0&&< 0.37.4	0.37.4`go get github.com/tilt-dev/tilt@v0.37.4`

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/tilt-dev/tilt, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update github.com/tilt-dev/tilt to 0.37.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-55883 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.

Frequently Asked Questions

## Summary The Tilt HUD WebSocket (`/ws/view`) is gated by a CSRF token, but the token is served by an unauthenticated endpoint and the upgrader accepts any client that omits an `Origin` header. When the HUD is network-exposed, an attacker can open the HUD stream and read the developer's session state. ## Details The upgrader accepts a connection when the `csrf` query parameter matches a process-wide token (`websocketCSRFToken`). That token is served as `text/plain` by an unauthenticated handler (`WebsocketToken`, mounted at `/api/websocket_token`), so any reachable caller can fetch it and co

O3 Security · Impact-Aware SCA

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