CVE-2026-90052 — Linux kernel
HIGHCVE-2026-90052 is a high-severity (CVSS 7.8) remote code execution vulnerability. A fix is available — see the affected versions and patch details below.
dm-integrity: fix buffer overflow with keyed discard
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2026-90052 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 376,715 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Description
In the Linux kernel, the following vulnerability has been resolved:
dm-integrity: fix buffer overflow with keyed discard
Since commit 68c5c42567bc ("dm-integrity: replace forgeable discard filler with a keyed sector marker"), integrity_metadata computes a checksum for every discarded block into the "checksums" buffer. integrity_sector_checksum always writes the whole digest. So if the tag size is smaller than the digest size, the checksum of the last block that fits into the buffer is written past the end of it. For example, with hmac(sha256) and tag size 16, a 4MiB discard writes 16 bytes past the kmalloc'ed page.
Fix this by subtracting extra_space from the buffer size when computing max_blocks, like we do for writes.
Detection & mitigation playbook
VulnerabilityDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for the affected component, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
No patched version of the affected component has shipped for CVE-2026-90052 yet. Where your build allows, override or pin the dependency away from the vulnerable range, and apply any maintainer-recommended mitigation.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2026-90052 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2026-90052. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-90052 in your dependencies?
O3 Security finds CVE-2026-90052 across dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.