GHSA-39Q5-4VQC-9P73
Vulnerability from github – Published: 2025-08-19 18:31 – Updated: 2025-11-03 18:31In the Linux kernel, the following vulnerability has been resolved:
pptp: ensure minimal skb length in pptp_xmit()
Commit aabc6596ffb3 ("net: ppp: Add bound checking for skb data on ppp_sync_txmung") fixed ppp_sync_txmunge()
We need a similar fix in pptp_xmit(), otherwise we might read uninit data as reported by syzbot.
BUG: KMSAN: uninit-value in pptp_xmit+0xc34/0x2720 drivers/net/ppp/pptp.c:193 pptp_xmit+0xc34/0x2720 drivers/net/ppp/pptp.c:193 ppp_channel_bridge_input drivers/net/ppp/ppp_generic.c:2290 [inline] ppp_input+0x1d6/0xe60 drivers/net/ppp/ppp_generic.c:2314 pppoe_rcv_core+0x1e8/0x760 drivers/net/ppp/pppoe.c:379 sk_backlog_rcv+0x142/0x420 include/net/sock.h:1148 __release_sock+0x1d3/0x330 net/core/sock.c:3213 release_sock+0x6b/0x270 net/core/sock.c:3767 pppoe_sendmsg+0x15d/0xcb0 drivers/net/ppp/pppoe.c:904 sock_sendmsg_nosec net/socket.c:712 [inline] __sock_sendmsg+0x330/0x3d0 net/socket.c:727 _syssendmsg+0x893/0xd80 net/socket.c:2566 _sys_sendmsg+0x271/0x3b0 net/socket.c:2620 __sys_sendmmsg+0x2d9/0x7c0 net/socket.c:2709
{
"affected": [],
"aliases": [
"CVE-2025-38574"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2025-08-19T17:15:34Z",
"severity": null
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\npptp: ensure minimal skb length in pptp_xmit()\n\nCommit aabc6596ffb3 (\"net: ppp: Add bound checking for skb data\non ppp_sync_txmung\") fixed ppp_sync_txmunge()\n\nWe need a similar fix in pptp_xmit(), otherwise we might\nread uninit data as reported by syzbot.\n\nBUG: KMSAN: uninit-value in pptp_xmit+0xc34/0x2720 drivers/net/ppp/pptp.c:193\n pptp_xmit+0xc34/0x2720 drivers/net/ppp/pptp.c:193\n ppp_channel_bridge_input drivers/net/ppp/ppp_generic.c:2290 [inline]\n ppp_input+0x1d6/0xe60 drivers/net/ppp/ppp_generic.c:2314\n pppoe_rcv_core+0x1e8/0x760 drivers/net/ppp/pppoe.c:379\n sk_backlog_rcv+0x142/0x420 include/net/sock.h:1148\n __release_sock+0x1d3/0x330 net/core/sock.c:3213\n release_sock+0x6b/0x270 net/core/sock.c:3767\n pppoe_sendmsg+0x15d/0xcb0 drivers/net/ppp/pppoe.c:904\n sock_sendmsg_nosec net/socket.c:712 [inline]\n __sock_sendmsg+0x330/0x3d0 net/socket.c:727\n ____sys_sendmsg+0x893/0xd80 net/socket.c:2566\n ___sys_sendmsg+0x271/0x3b0 net/socket.c:2620\n __sys_sendmmsg+0x2d9/0x7c0 net/socket.c:2709",
"id": "GHSA-39q5-4vqc-9p73",
"modified": "2025-11-03T18:31:33Z",
"published": "2025-08-19T18:31:33Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-38574"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/1a04db0fd75cb6034fc27a56b67b3b8b9022a98c"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/26672f1679b143aa34fca0b6046b7fd0c184770d"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/5005d24377378a20e5c0e53052fc4ebdcdcbc611"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/504cc4ab91073d2ac7404ad146139f86ecee7193"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/5de7513f38f3c19c0610294ee478242bea356f8c"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/97b8c5d322c5c0038cac4bc56fdbe237d0be426f"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/b7dcda76fd0615c0599c89f36873a6cd48e02dbb"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/de9c4861fb42f0cd72da844c3c34f692d5895b7b"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/ea99b88b1999ebcb24d5d3a6b7910030f40d3bba"
},
{
"type": "WEB",
"url": "https://lists.debian.org/debian-lts-announce/2025/10/msg00007.html"
},
{
"type": "WEB",
"url": "https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html"
}
],
"schema_version": "1.4.0",
"severity": []
}
Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.