CVE-2026-72025 — s390/monwriter: Reject buffer reuse with different data length
In the Linux kernel, the following vulnerability has been resolved: s390/monwriter: Reject buffer reuse with different data length When data buffers are reused, e.g. for interval sample records, the first record determines the data length, and the size of the buffer for user copy. Current monwriter code does not check if the data length was changed for subsequent records, which also would never happen for valid user programs. However, a malicious user could change the data length, resulting in out of bounds user copy to the kernel buffer, and memory corruption. By default, the monwriter misc device is created with root-only permissions, so practical impact is typically low. Fix this by checking for changed data length and rejecting such records.
Who exploits it and how urgent it is
A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.
How the score was calculated
- EPSS 0.2% (30-day exploitation probability)+2
The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.
Remediation
Fixes and mitigations documented by the sources — linked to the original advisory.
No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.
First 24 hours
Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.
- Identify exposed assets running the affected vendor/product/version combinations (Linux Linux).
- No fix documented in the sources: reduce exposure and monitor the vendor advisory.
- Search available logs for exploit probes, errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
| Vendor | Product | Versions | Status | Source |
|---|---|---|---|---|
| Linux | Linux |
≥ 31b58088292c7f00f0b81088bfb557285b0b6247 and < 096dff1247037d329c04b3a5be0ecdfb1c5c7ac6≥ 31b58088292c7f00f0b81088bfb557285b0b6247 and < d39cf4a6d721b1ae21eb53bbf3e8cd984253d7ab≥ 31b58088292c7f00f0b81088bfb557285b0b6247 and < 759d91378203ea35fa9bca6726dcf0010de081fb≥ 31b58088292c7f00f0b81088bfb557285b0b6247 and < 036bc5661060702e798d215e81bb46da530965b3≥ 31b58088292c7f00f0b81088bfb557285b0b6247 and < 01f3ce411711c2c919598ea25320a5a48f71edbc≥ 31b58088292c7f00f0b81088bfb557285b0b6247 and < f0745496f7c171271cafd9457df3b914a483ddeb≥ 31b58088292c7f00f0b81088bfb557285b0b6247 and < ae5347f3db1782c6118f6cc0d9fd8b1d43397db3≥ 31b58088292c7f00f0b81088bfb557285b0b6247 and < 2995ccec260caa9e85b3301a4aba1e66ed80ad74 and 1 moreversion 2.6.19 |
Vulnerable | CVE Program (cve.org) e CISA ADP |
EPSS over time FIRST
Oct 15, 2026 → Oct 30, 2026 · 15 reading(s) · max 0.22%
Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Not enough vector or weakness data: use the affected application’s logs as a starting point.
Timeline
What happened to this CVE, newest first.
- 2026
- Record published
- Affected products added · linux/linux
- Source status changed · → Received
- Record created in this database
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 1× Official description updated · Oct 15, 2026 – Oct 15, 2026
References
8 on the record
- git.kernel.org/stable/c/036bc5661060702e798d215e81bb46da530965b3
- git.kernel.org/stable/c/2995ccec260caa9e85b3301a4aba1e66ed80ad74
- git.kernel.org/stable/c/ae5347f3db1782c6118f6cc0d9fd8b1d43397db3
- git.kernel.org/stable/c/01f3ce411711c2c919598ea25320a5a48f71edbc
- git.kernel.org/stable/c/759d91378203ea35fa9bca6726dcf0010de081fb
- git.kernel.org/stable/c/d39cf4a6d721b1ae21eb53bbf3e8cd984253d7ab
- git.kernel.org/stable/c/096dff1247037d329c04b3a5be0ecdfb1c5c7ac6
- git.kernel.org/stable/c/f0745496f7c171271cafd9457df3b914a483ddeb
Elsewhere on this site
Related CVEs (same products)
- Unknown CVE-2026-99216 Drivers: hv: Don't reset VMBus connection state on error/exit paths 2d
- Unknown CVE-2026-99215 power: supply: core: prevent unregistering a power supply while a callback runs 2d
- Unknown CVE-2026-99207 scsi: target: Disable interrupts while holding delayed_cmd_lock 2d
- Unknown CVE-2026-99208 drm/xe/oa: Zero OA buffer at allocation 2d
- Unknown CVE-2026-99209 drm/xe: skip eviction of a BO with no resource 2d
- Unknown CVE-2026-99210 accel/rocket: clear rdev on device init failure 2d
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No CVSS score published by NVD, the CNA, CISA or GitHub so far.
- No fixed version, patch or mitigation documented.
- No CISA SSVC assessment.
- No CWE classification.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record
Text assembled only from the fields above — no additional claims.
What should defenders know first?
CVE-2026-72025 is "s390/monwriter: Reject buffer reuse with different data length", rated Unknown. It affects Linux (Linux); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. EPSS 0.22% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.
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