Bluetooth: RFCOMM: Reject short EA=0 frames in rfcomm_recv_frame()
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: RFCOMM: Reject short EA=0 frames in rfcomm_recv_frame() While rfcomm_recv_frame() verifies that skb->len is at least sizeof(*hdr) + 1 (4 bytes: 3-byte header + 1-byte FCS), an RFCOMM frame with an extended 2-byte length field (!__test_ea(hdr->len)) has a 4-byte header plus a 1-byte FCS (5 bytes minimum, sizeof(*hdr) + 2). When a 4-byte RFCOMM frame with EA == 0 arrives: 1. The initial skb->len < sizeof(*hdr) + 1 check passes (4 < 4 is false). 2. Trimming the FCS byte decrements skb->len to 3. 3. If __check_fcs() succeeds, skb_pull(skb, 4) fails (4 > 3) and returns NULL without advancing skb->data. 4. Because the return value of skb_pull() is ignored, the un-pulled 3-byte struct rfcomm_hdr remains at skb->data and is either queued as application payload via rfcomm_recv_data() or parsed as a multiplexer control command via rfcomm_recv_mcc() on DLCI 0. Fix this by extending the length check in rfcomm_recv_frame() to also require skb->len >= sizeof(*hdr) + 2 when !__test_ea(hdr->len).
CVE-2026-98600
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-98600
Linux
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Linux
Source reference: /containers/cna/affected/1/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "fb40eda15122f6b780228639c1ead6820340ff54",
"lessThan": "76876fd26569302d26d91cbe8b75fa8e66cf8969",
"versionType": "git"
},
{
"status": "affected",
"version": "3829af5fab5a22405bf1e7d69068c2ec0fce46ca",
"lessThan": "97711b964877242933484989224a3c4c5d88a5ee",
"versionType": "git"
},
{
"status": "affected",
"version": "b161eacd7fa4a2d765724b5504ac6cc388e48f80",
"lessThan": "7a1781a2f3a9667b3065d402d1f11986a2363e08",
"versionType": "git"
},
{
"status": "affected",
"version": "30d1d9f3495463f7c026e4c553127f79b486fcd6",
"lessThan": "c25587fa26761e623198b4f47151fe79d09ccde6",
"versionType": "git"
},
{
"status": "affected",
"version": "67dc3b40fae71b6b11c71e7ff69bac0758818c05",
"lessThan": "71ccacde407b7d8f0ef48974a0d2524602fd5c44",
"versionType": "git"
},
{
"status": "affected",
"version": "bbc310caa2b6bf5fe42896ba27da0fbc12e4ac51",
"lessThan": "be00deee60044ffa820f9436415caeb665b2cda0",
"versionType": "git"
},
{
"status": "affected",
"version": "b230e5bf501c5edaf2eb0991cb862ac142031d4b",
"lessThan": "9240fc1f2cde5331c61608da21b00394602ca762",
"versionType": "git"
},
{
"status": "affected",
"version": "b230e5bf501c5edaf2eb0991cb862ac142031d4b",
"lessThan": "6d91041bb38b97e2feb625123cc0529d7b83a0e1",
"versionType": "git"
},
{
"status": "affected",
"version": "6.12.111",
"lessThan": "6.12.112",
"versionType": "semver"
},
{
"status": "affected",
"version": "6.18.53",
"lessThan": "6.18.55",
"versionType": "semver"
}
],
"programFiles": [
"net/bluetooth/rfcomm/core.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "7.2"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "7.2",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "6.12.112",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.55",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.2.9",
"versionType": "semver",
"lessThanOrEqual": "7.2.*"
},
{
"status": "unaffected",
"version": "7.3",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"net/bluetooth/rfcomm/core.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-98600
Source reference:
/cveMetadata/cveId
Publisher severity
No explicit severity was provided.
- Event
- #38620 · Revision 1
- Added to Heist Feed
- Publisher date