Critical
Security advisory
In ACCEL-PPP (an implementation of PPTP/PPPoE/L2TP/SSTP), there is a buffer overflow when receiving an l2tp control packet ith an AVP which type is a string and no hidden flags, length set to less than 6. If your application is used in open networks or there are untrusted nodes in the network it is highly recommended to apply the patch. The problem was patched with commit 2324bcd5ba12cf28f47357a8f03cd41b7c04c52b As a workaround changes of commit 2324bcd5ba12cf28f47357a8f03cd41b7c04c52b can be applied to older versions.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2020-15173
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 12:34 UTC · Revision 1
Source evidence
In ACCEL-PPP (an implementation of PPTP/PPPoE/L2TP/SSTP), there is a buffer overflow when receiving an l2tp control packet ith an AVP which type is a string and no hidden flags, length set to less than 6. If your application is used in open networks or there are untrusted nodes in the network it is highly recommended to apply the patch. The problem was patched with commit 2324bcd5ba12cf28f47357a8f03cd41b7c04c52b As a workaround changes of commit 2324bcd5ba12cf28f47357a8f03cd41b7c04c52b can be applied to older versions.
osv:CVE-2020-15173
Complete source record
{
"id": "89e846834e59bb150bc1422db4599adfb142089f7f0f67c5ed367c501ffa1c5a",
"url": "https://osv.dev/vulnerability/CVE-2020-15173",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "CVE-2020-15173",
"summary": "In ACCEL-PPP (an implementation of PPTP/PPPoE/L2TP/SSTP), there is a buffer overflow when receiving an l2tp control packet ith an AVP which type is a string and no hidden flags, length set to less than 6. If your application is used in open networks or there are untrusted nodes in the network it is highly recommended to apply the patch. The problem was patched with commit 2324bcd5ba12cf28f47357a8f03cd41b7c04c52b As a workaround changes of commit 2324bcd5ba12cf28f47357a8f03cd41b7c04c52b can be applied to older versions.",
"evidence": "osv:CVE-2020-15173",
"products": [],
"severity": "critical",
"structured": {
"id": "CVE-2020-15173",
"aliases": [
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"GHSA-rr68-fchr-69vf"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"
}
],
"affected": [
{
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{
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},
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},
{
"id": "CVE-2020-15173-da118e96",
"digest": {
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"target": {
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"signature_type": "Function",
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"vanir_signatures_modified": "2026-10-20T13:52:27Z"
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],
"modified": "2026-10-20T13:52:27.555248152Z",
"provider": "osv",
"references": [
"https://github.com/accel-ppp/accel-ppp/security/advisories/GHSA-rr68-fchr-69vf",
"https://github.com/accel-ppp/accel-ppp/commit/2324bcd5ba12cf28f47357a8f03cd41b7c04c52b"
],
"provider_metadata": {
"unresolved_ranges": [
{
"cpes": [
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],
"vendor_product": "accel-ppp:accel-ppp",
"extracted_events": [
{
"range": [
{
"last_affected": "1.12.0-92-g38b6104"
}
],
"source": "CPE_RANGE"
}
]
}
]
}
},
"related_cves": [
{
"value": "CVE-2020-15173",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 388317,
"published_at": "2020-09-09T23:15:10.977+00:00"
}