CVE-2026-98380
Status: ReceivedUnscored—
In the Linux kernel, the following vulnerability has been resolved:
net/sched: reject IDR error pointers when deleting actions
tcf_action_delete() drops the reference held by its lookup before calling tcf_idr_delete_index() with the saved action index. An unlocked classifier can remove that action and reserve the same IDR slot with ERR_PTR(-EBUSY) in between.
tcf_idr_delete_index() only checks the lookup result for NULL. It therefore treats the reservation as a tc_action and dereferences tcfa_bindcnt. A hardware execution breakpoint was used to schedule the interleaving without changing the kernel source. KASAN reported this decoded trace:
Read full descriptionShow less
R15 contains ERR_PTR(-EBUSY), and adding the tcfa_bindcnt offset produces the address in R13. With the guard applied, the same reproducer returned -ENOENT without a KASAN report or panic. Treat error pointers as absent and return -ENOENT.
Technical details traces, logs and code from the original report
BUG: KASAN: null-ptr-deref in tca_action_gd+0x5b9/0x1010
Read of size 4 at addr 0000000000000010 by task poc/150
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000002
RIP: tca_action_gd+0x5c0/0x1010:
arch_atomic_read at arch/x86/include/asm/atomic.h:23
raw_atomic_read at include/linux/atomic/atomic-arch-fallback.h:457
atomic_read at include/linux/atomic/atomic-instrumented.h:33
tcf_idr_delete_index at net/sched/act_api.c:766
tcf_action_delete at net/sched/act_api.c:1859
tcf_del_notify at net/sched/act_api.c:2014
tca_action_gd at net/sched/act_api.c:2064
R13: 0000000000000010 R15: fffffffffffffff0
Kernel panic - not syncing: Fatal exceptionCVSS
NVD hasn't assigned a CVSS score to this CVE (common since the April 2026 policy change).
Exploitation probability (EPSS)
- Probability of exploitation in the next 30 days: 0.18%
- Percentile among all scored CVEs: 7
- Score date: 10/13/2026
EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).
Affected technologies (1)
⚠ AI-inferred from the description — NVD hasn't analyzed this CVE yet, these aren't verified CPEs.
References
- https://git.kernel.org/stable/c/259caa711b7688365676442e2fdb286b8aceaa80
- https://git.kernel.org/stable/c/39b751a210bf61a374afa82749afc7a77a08bf1d
- https://git.kernel.org/stable/c/6bf076258aac4e0af69ef317656c31ce6444d647
- https://git.kernel.org/stable/c/6c9f07bf8800171de2cd3f02815cebe1f4d45f2d
- https://git.kernel.org/stable/c/968550a439f64bd1a6c0d88efb92e4f082f84a26
- https://git.kernel.org/stable/c/a9551f26287debe6d8aa6e8841974661065b975f
- https://git.kernel.org/stable/c/c82b797abe668d0b668601a93ba2c0b071a63574
- https://git.kernel.org/stable/c/dd80a7519824b72c8fcfd3cc50cb93f7e2d90923
Raw JSON (NVD)
Show
{
"id": "CVE-2026-98380",
"cveTags": [],
"metrics": {},
"affected": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"affectedData": [
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "0190c1d452a91c38a3462abdd81752be1b9006a8",
"lessThan": "39b751a210bf61a374afa82749afc7a77a08bf1d",
"versionType": "git"
},
{
"status": "affected",
"version": "0190c1d452a91c38a3462abdd81752be1b9006a8",
"lessThan": "dd80a7519824b72c8fcfd3cc50cb93f7e2d90923",
"versionType": "git"
},
{
"status": "affected",
"version": "0190c1d452a91c38a3462abdd81752be1b9006a8",
"lessThan": "6bf076258aac4e0af69ef317656c31ce6444d647",
"versionType": "git"
},
{
"status": "affected",
"version": "0190c1d452a91c38a3462abdd81752be1b9006a8",
"lessThan": "6c9f07bf8800171de2cd3f02815cebe1f4d45f2d",
"versionType": "git"
},
{
"status": "affected",
"version": "0190c1d452a91c38a3462abdd81752be1b9006a8",
"lessThan": "259caa711b7688365676442e2fdb286b8aceaa80",
"versionType": "git"
},
{
"status": "affected",
"version": "0190c1d452a91c38a3462abdd81752be1b9006a8",
"lessThan": "968550a439f64bd1a6c0d88efb92e4f082f84a26",
"versionType": "git"
},
{
"status": "affected",
"version": "0190c1d452a91c38a3462abdd81752be1b9006a8",
"lessThan": "a9551f26287debe6d8aa6e8841974661065b975f",
"versionType": "git"
},
{
"status": "affected",
"version": "0190c1d452a91c38a3462abdd81752be1b9006a8",
"lessThan": "c82b797abe668d0b668601a93ba2c0b071a63574",
"versionType": "git"
}
],
"programFiles": [
"net/sched/act_api.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "4.19"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "4.19",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "5.10.271",
"versionType": "semver",
"lessThanOrEqual": "5.10.*"
},
{
"status": "unaffected",
"version": "5.15.222",
"versionType": "semver",
"lessThanOrEqual": "5.15.*"
},
{
"status": "unaffected",
"version": "6.1.189",
"versionType": "semver",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.6.158",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"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-rc5",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"net/sched/act_api.c"
],
"defaultStatus": "affected"
}
]
}
],
"published": "2026-10-09T08:16:56.400",
"references": [
{
"url": "https://git.kernel.org/stable/c/259caa711b7688365676442e2fdb286b8aceaa80",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/39b751a210bf61a374afa82749afc7a77a08bf1d",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/6bf076258aac4e0af69ef317656c31ce6444d647",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/6c9f07bf8800171de2cd3f02815cebe1f4d45f2d",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/968550a439f64bd1a6c0d88efb92e4f082f84a26",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/a9551f26287debe6d8aa6e8841974661065b975f",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/c82b797abe668d0b668601a93ba2c0b071a63574",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/dd80a7519824b72c8fcfd3cc50cb93f7e2d90923",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
],
"vulnStatus": "Received",
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: reject IDR error pointers when deleting actions\n\ntcf_action_delete() drops the reference held by its lookup before calling\ntcf_idr_delete_index() with the saved action index. An unlocked\nclassifier can remove that action and reserve the same IDR slot with\nERR_PTR(-EBUSY) in between.\n\ntcf_idr_delete_index() only checks the lookup result for NULL. It\ntherefore treats the reservation as a tc_action and dereferences\ntcfa_bindcnt. A hardware execution breakpoint was used to schedule the\ninterleaving without changing the kernel source. KASAN reported this\ndecoded trace:\n\n BUG: KASAN: null-ptr-deref in tca_action_gd+0x5b9/0x1010\n Read of size 4 at addr 0000000000000010 by task poc/150\n Oops: general protection fault, probably for non-canonical address 0xdffffc0000000002\n RIP: tca_action_gd+0x5c0/0x1010:\n arch_atomic_read at arch/x86/include/asm/atomic.h:23\n raw_atomic_read at include/linux/atomic/atomic-arch-fallback.h:457\n atomic_read at include/linux/atomic/atomic-instrumented.h:33\n tcf_idr_delete_index at net/sched/act_api.c:766\n tcf_action_delete at net/sched/act_api.c:1859\n tcf_del_notify at net/sched/act_api.c:2014\n tca_action_gd at net/sched/act_api.c:2064\n R13: 0000000000000010 R15: fffffffffffffff0\n Kernel panic - not syncing: Fatal exception\n\nR15 contains ERR_PTR(-EBUSY), and adding the tcfa_bindcnt offset produces\nthe address in R13. With the guard applied, the same reproducer returned\n-ENOENT without a KASAN report or panic. Treat error pointers as absent\nand return -ENOENT."
}
],
"lastModified": "2026-10-09T08:16:56.400",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}