GHSA-FP35-JCPC-9WWG
Vulnerability from github – Published: 2026-06-25 09:31 – Updated: 2026-06-28 09:31In the Linux kernel, the following vulnerability has been resolved:
rxrpc: Fix the ACK parser to extract the SACK table for parsing
Fix modification of the received skbuff in rxrpc_input_soft_acks() and a potential incorrect access of the buffer in a fragmented UDP packet (the packet would probably have to be deliberately pre-generated as fragmented) when AF_RXRPC tries to extract the contents of the SACK table by copying out the contents of the SACK table into a buffer before attempting to parse
AF_RXRPC assumes that it can just call skb_condense() and then validly access the SACK table from skb->data and that it will be a flat buffer - but skb_condense() can silently fail to do anything under some circumstances.
Note that whilst rxrpc_input_soft_acks() should be able to parse extended ACKs, the rest of AF_RXRPC doesn't currently support that.
Further, there's then no need to call skb_condense() in rxrpc_input_ack(), so don't.
{
"affected": [],
"aliases": [
"CVE-2026-53151"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-06-25T09:16:32Z",
"severity": "CRITICAL"
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\nrxrpc: Fix the ACK parser to extract the SACK table for parsing\n\nFix modification of the received skbuff in rxrpc_input_soft_acks() and a\npotential incorrect access of the buffer in a fragmented UDP packet (the\npacket would probably have to be deliberately pre-generated as fragmented)\nwhen AF_RXRPC tries to extract the contents of the SACK table by copying\nout the contents of the SACK table into a buffer before attempting to parse\n\nAF_RXRPC assumes that it can just call skb_condense() and then validly\naccess the SACK table from skb-\u003edata and that it will be a flat buffer -\nbut skb_condense() can silently fail to do anything under some\ncircumstances.\n\nNote that whilst rxrpc_input_soft_acks() should be able to parse extended\nACKs, the rest of AF_RXRPC doesn\u0027t currently support that.\n\nFurther, there\u0027s then no need to call skb_condense() in rxrpc_input_ack(),\nso don\u0027t.",
"id": "GHSA-fp35-jcpc-9wwg",
"modified": "2026-06-28T09:31:42Z",
"published": "2026-06-25T09:31:19Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-53151"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/224298450be5c04d2a6ea1c2a94669d7ebf65d00"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/333b6d5bb9f87827ac2639c737bf9613dbae7253"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/566c4c1244de50fbff1f89ff93c9d7b0fc256db4"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
Sightings
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