# CVE-2026-77322: SIPGO DoS via unvalidated WebSocket frame length

Source: https://junglewise.ai/threats/cve-2026-77322-sipgo-dos-via-unvalidated-websocket-frame-length  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-22. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

CVE-2026-77322 · Severity: high · CVSS 7.5 · Published 2026-09-22

SIPGO is a SIP protocol library used to build telephony and VoIP applications. A vulnerability in its WebSocket transport allows an unauthenticated attacker to crash the entire server process by sending a malformed WebSocket frame with an extremely large declared payload length. This causes immediate service outage and can be triggered repeatedly without authentication.

Technologies: [github.com/emiago/sipgo (Go)](https://junglewise.ai/threats/technologies/github-com-emiago-sipgo). Vendors: [Go](https://junglewise.ai/threats/vendors/go).

## Quick answers

**Is CVE-2026-77322 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-77322 being exploited in the wild.

**How severe is CVE-2026-77322?** High severity, with a CVSS score of 7.5, published 22 September 2026.

**Which products and versions are affected?** github.com/emiago/sipgo (Go) <= 1.4.2, SEMVER:introduced=0,fixed=1.4.3.

**Is there a fix for CVE-2026-77322?** Yes. github.com/emiago/sipgo (Go): upgrade to 1.4.3 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-77322 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-77322?** Check whether you run github.com/emiago/sipgo (Go) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- github.com/emiago/sipgo (Go): upgrade to 1.4.3 or later

  ```sh
  go get github.com/emiago/sipgo@v1.4.3
  ```


## Technical details

The vulnerability exists in WSConnection.Read, which allocates a buffer based on the WebSocket frame header's declared length field before validating the value. The length field is client-controlled and can be up to 2^63-1 (signed 64-bit integer). When an attacker sends a frame declaring an excessively large length (e.g., 2^63-1), the make() call panics due to slice size limits. SIPGO does not recover from this panic, crashing the entire server process. The attack requires only network reachability and a completed WebSocket handshake; no authentication is needed. The fix is to set MaxFrameSize limits on the wsutil.NewReader call.

## Affected products

- SIPGO sipgo up to v1.4.0

## Identifiers

- CVE-2026-77322
- GHSA-8h6x-h86x-75wh
- GO-2026-6559

## Timeline

- 2026-09-22: disclosed: GitHub advisory GHSA-8h6x-h86x-75wh published
- 2026: other: CVE-2026-77322 assigned

## Related threats

- [SIPGO DoS via unvalidated Content-Length in stream parser](https://junglewise.ai/threats/cve-2026-58268-sipgo-dos-via-unvalidated-content-length-in-stream-parser)
- [GO-2025-4244 - SIPGO is Vulnerable to Response DoS via Nil Pointer Dereference in github.com/emiago/sipgo](https://junglewise.ai/threats/cve-2025-68274-sipgo-is-vulnerable-to-response-dos-via-nil-pointer-dereference)