SIPGO: DoS via unvalidated WebSocket frame length

CISA KEV is observed exploitation evidence. FIRST EPSS is a dated prediction of exploitation in the next 30 days. Missing scores are unknown. This collector requests predictions only for explicit CVE aliases in the public NuGet archive; Microsoft release views retain their existing prediction scope.

No collected risk observation for these identifiers. This does not establish absence of exploitation or a zero probability.

SIPGO is a library for writing SIP services in the GO language. Prior to 1.4.3, WSConnection.Read in sip/transport_ws.go creates a wsutil.Reader without setting MaxFrameSize, allowing NextFrame to accept a client-controlled header.Length before ParseMaxMessageLength is applied. An unauthenticated WS or WSS peer can send a frame header declaring an extremely large payload, causing an oversized allocation or a makeslice length panic before the payload is read and crashing or exhausting memory in the server process. This issue is fixed in version 1.4.3.

Source published

22 Sep 2026 19:52:12 UTC

Source modified

23 Sep 2026 15:08:21 UTC

Observed here

23 Oct 2026 15:48:27 UTC

Source terms

CVE Program Terms of Use

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CVSS 3.1 · 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

SIPGO is a library for writing SIP services in the GO language. Prior to 1.4.3, WSConnection.Read in sip/transport_ws.go creates a wsutil.Reader without setting MaxFrameSize, allowing NextFrame to accept a client-controlled header.Length before ParseMaxMessageLength is applied. An unauthenticated WS or WSS peer can send a frame header declaring an extremely large payload, causing an oversized allocation or a makeslice length panic before the payload is read and crashing or exhausting memory in the server process. This issue is fixed in version 1.4.3.

Source published

Sep 22, 2026, 7:52:12 PM (timezone not stated)

Source modified

Sep 23, 2026, 3:08:21 PM (timezone not stated)

Observed here

11 Nov 2026 16:08:16 UTC

Source terms

ENISA EUVD · source terms and attribution apply

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This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: euvd · ENISA EUVD · source terms and attribution apply. Source text is retained; field grouping and change labels are provided by ChangeIntel.

EUVD CVSS 3.1 · 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

SIPGO is a library for writing SIP services in the GO language. Prior to 1.4.3, WSConnection.Read in sip/transport_ws.go creates a wsutil.Reader without setting MaxFrameSize, allowing NextFrame to accept a client-controlled header.Length before ParseMaxMessageLength is applied. An unauthenticated WS or WSS peer can send a frame header declaring an extremely large payload, causing an oversized allocation or a makeslice length panic before the payload is read and crashing or exhausting memory in the server process. This issue is fixed in version 1.4.3.

Source published

22 Sep 2026 20:17:08 UTC

Source modified

23 Sep 2026 18:12:04 UTC

Observed here

25 Oct 2026 16:19:04 UTC

Source terms

NIST NVD usage terms; underlying source attribution retained

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This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: nvd · NIST NVD usage terms; underlying source attribution retained. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS 3.1 · [email protected] · Secondary · 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

### Summary The WebSocket transport allocates a buffer from the frame payload length before validating its size, which can lead to an unauthenticated DoS. ### Details `WSConnection.Read` allocates a buffer from the declared WebSocket frame length before reading the payload (https://github.com/emiago/sipgo/blob/v1.4.0/sip/transport_ws.go#L400): ```go data := make([]byte, header.Length) // header.Length is client-controlled, up to 2^63-1 (int64) ``` - `NextFrame()` reads only the frame header and never checks the length: `wsutil.NewReader` is created with no [`MaxFrameSize`](https://pkg.go.dev/github.com/gobwas/[email protected]/wsutil#Reader.MaxFrameSize) (`0` = unlimited). `ParseMaxMessageLength` applies only downstream, not here. - A value above the max slice size (e.g. `2^63-1`) panics `make`. sipgo does not recover from this panic, so it crashes the whole server process. ### PoC Tested on emiago/sipgo v1.4.0 (latest). After a normal WebSocket handshake, send one masked text frame consisting of the header only (no payload), declaring a huge length. The allocation runs as soon as the header is read. ``` 0x81 FIN + text opcode 0xFF MASK bit + length marker 127 (8-byte length follows) 0x7F FF FF FF FF FF FF FF declared length = 2^63-1 -> make panics (crash) <4-byte masking key> (no payload) ``` This crashes the server process: ``` panic: runtime error: makeslice: len out of range goroutine 23 [running]: github.com/emiago/sipgo/sip.(*WSConnection).Read(...) /path/to/pkg/mod/github.com/emiago/[email protected]/sip/transport_ws.go:400 +0x2df github.com/emiago/sipgo/sip.(*TransportWS).readConnection(...) /path/to/pkg/mod/github.com/emiago/[email protected]/sip/transport_ws.go:194 +0x266 created by github.com/emiago/sipgo/sip.(*TransportWS).initConnection in goroutine 21 /path/to/pkg/mod/github.com/emiago/[email protected]/sip/transport_ws.go:167 +0x268 ``` ### Suggested Fix Set [`MaxFrameSize`](https://pkg.go.dev/github.com/gobwas/[email protected]/wsutil#Reader.MaxFrameSize) on the `wsutil.NewReader`. ### Impact Unauthenticated DoS. Any service using `sipgo` with a WS/WSS transport can be crashed by a single frame (panic), or forced to run out of memory.

Source published

22 Sep 2026 20:34:30 UTC

Source modified

1 Oct 2026 20:56:11 UTC

Observed here

24 Oct 2026 13:19:41 UTC

Source terms

GitHub Advisory Database · CC-BY-4.0

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This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: osv · GitHub Advisory Database · CC-BY-4.0. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS_V3 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Publisher rating · HIGH

SIPGO: DoS via unvalidated WebSocket frame length in github.com/emiago/sipgo

Source published

1 Oct 2026 20:23:38 UTC

Source modified

1 Oct 2026 20:45:13 UTC

Observed here

24 Oct 2026 13:19:41 UTC

Source terms

OSV · upstream source license applies

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: osv · OSV · upstream source license applies. Source text is retained; field grouping and change labels are provided by ChangeIntel.