bpf: Mark NULL kptr stores precise
In the Linux kernel, the following vulnerability has been resolved: bpf: Mark NULL kptr stores precise check_map_kptr_access() permits a scalar store into an untrusted kptr field only when the register is known to contain zero. Unlike other verifier checks whose outcome depends on a scalar value, it does not mark that register precise. A state checkpoint reached with an imprecise zero can therefore prune a second path that reaches the store with an arbitrary nonzero scalar. The program can write attacker-controlled bits into the kptr field and load them back as a PTR_TO_BTF_ID. Call mark_chain_precision() before accepting a known-zero register. This forces state equivalence to compare its scalar range and makes the verifier visit and reject a path carrying a nonzero value.
CVE-2026-98034
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-2026-98034
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": "61df10c7799e27807ad5e459eec9d77cddf8bf45",
"lessThan": "86a3171c90bfc35a54e9d83cd197ca0d72d2f4e4",
"versionType": "git"
},
{
"status": "affected",
"version": "61df10c7799e27807ad5e459eec9d77cddf8bf45",
"lessThan": "b8b98d3d37908402ff63515fa4d7574235436ea8",
"versionType": "git"
},
{
"status": "affected",
"version": "61df10c7799e27807ad5e459eec9d77cddf8bf45",
"lessThan": "bb667eb575c906f24c707986541a99424c5b07ea",
"versionType": "git"
},
{
"status": "affected",
"version": "61df10c7799e27807ad5e459eec9d77cddf8bf45",
"lessThan": "86168208737bdd267d92d855d453d1d2f840df19",
"versionType": "git"
},
{
"status": "affected",
"version": "61df10c7799e27807ad5e459eec9d77cddf8bf45",
"lessThan": "ecdc5043794c9184aa8e6c814603899479c46b35",
"versionType": "git"
},
{
"status": "affected",
"version": "b5a8069835e5236824a84281592d29f859b33153",
"versionType": "git"
},
{
"status": "affected",
"version": "5.18.18",
"lessThan": "5.19",
"versionType": "semver"
}
],
"programFiles": [
"kernel/bpf/verifier.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "5.19"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "5.19",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "6.6.160",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.114",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.57",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.2.7",
"versionType": "semver",
"lessThanOrEqual": "7.2.*"
},
{
"status": "unaffected",
"version": "7.3",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"kernel/bpf/verifier.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-98034
Source reference:
/cveMetadata/cveId
Publisher severity
No explicit severity was provided.
- Event
- #48832 · Revision 1
- Added to Heist Feed
- Publisher date