CVE-2025-38708 | drbd: add missing kref_get in handle_write_conflicts

In the Linux kernel, the following vulnerability has been resolved: drbd: add missing kref_get in handle_write_conflicts With `two-primaries` enabled, DRBD tries to detect "concurrent" writes and handle write conflicts, so that even if you write to the same sector simultaneously on both nodes, they end up with the identical data once the writes are completed. In handling "superseeded" writes, we forgot a kref_get, resulting in a premature drbd_destroy_device and use after free, and further to kernel crashes with symptoms. Relevance: No one should use DRBD as a random data generator, and apparently all users of "two-primaries" handle concurrent writes correctly on layer up. That is cluster file systems use some distributed lock manager, and live migration in virtualization environments stops writes on one node before starting writes on the other node. Which means that other than for "test cases", this code path is never taken in real life. FYI, in DRBD 9, things are handled differently nowadays. We still detect "write conflicts", but no longer try to be smart about them. We decided to disconnect hard instead: upper layers must not submit concurrent writes. If they do, that's their fault.

Published: 2025-09-04 Last update: 2026-05-12 Assigner: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67

Conclusion & alert: CVE-2025-38708 is rated Low Risk (33.5/100): CVSS High severity, with low exploitation likelihood (EPSS 0.03%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2025-38708

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-01-29 0.07% 0.03% -0.04%
2 2025-11-21 0.05% 0.07% +0.02%
3 2025-11-18 0.05%

Full EPSS history (5 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2025-38708

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.8 3.1 HIGH
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
1.8 5.9 [email protected]

Weakness enumeration for CVE-2025-38708

GitHub Security Advisory for CVE-2025-38708

GHSA-5jqr-8vwq-w36c · Severity: high — In the Linux kernel, the following vulnerability has been resolved: drbd: add missing kref_get...

OS Trackers for CVE-2025-38708

vendor priority summary link
debian not yet assigned CVE-2025-38708 not yet assigned priority: Debian including 2 source packages (linux, linux-6.1), 6 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 6. https://security-tracker.debian.org/tracker/CVE-2025-38708
redhat https://access.redhat.com/security/cve/CVE-2025-38708
suse medium CVE-2025-38708 severity moderate: SUSE including 26 source package names (cluster-md-kmp-default, dlm-kmp-default, …), 276 product×package rows across 54 product lines (SLES-LTSS-TERADATA 15 SP2, SUSE Linux Enterprise High Availability Extension 15 SP7, … (54 product lines)): Known Not Affected 276. https://www.suse.com/security/cve/CVE-2025-38708/
ubuntu medium CVE-2025-38708 medium priority: Ubuntu including 158 source packages (linux, linux-allwinner-5.19, …), 1414 status rows across 9 suites (bionic, focal, jammy, noble, plucky, questing, trusty, upstream, xenial): DNE 1017, ignored 180, released 150, needed 48, not-affected 16, needs-triage 2, pending 1. https://ubuntu.com/security/CVE-2025-38708

Affected software / configurations for CVE-2025-38708

Vendor Product Version Raw CPE
linux linux_kernel >= 4.5, < 5.4.297 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 5.5, < 5.10.241 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 5.11, < 5.15.190 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 5.16, < 6.1.149 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 6.2, < 6.6.103 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 6.7, < 6.12.43 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 6.13, < 6.15.11 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 6.16, < 6.16.2 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
debian debian_linux 11.0 cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*

References for CVE-2025-38708

URL Tags
https://git.kernel.org/stable/c/00c9c9628b49e368d140cfa61d7df9b8922ec2a8 Patch
https://git.kernel.org/stable/c/0336bfe9c237476bd7c45605a36ca79c2bca62e5 Patch
https://git.kernel.org/stable/c/3a896498f6f577e57bf26aaa93b48c22b6d20c20 Patch
https://git.kernel.org/stable/c/46e3763dcae0ffcf8fcfaff4fc10a90a92ffdd89 Patch
https://git.kernel.org/stable/c/57418de35420cedab035aa1da8a26c0499b7f575 Patch
https://git.kernel.org/stable/c/7d483ad300fc0a06f69b019dda8f74970714baf8 Patch
https://git.kernel.org/stable/c/810cd546a29bfac90ed1328ea01d693d4bd11cb1 Patch
https://git.kernel.org/stable/c/84ef8dd3238330d1795745ece83b19f0295751bf Patch
https://git.kernel.org/stable/c/9f53b2433ad248cd3342cc345f56f5c7904bd8c4 Patch
https://lists.debian.org/debian-lts-announce/2025/10/msg00007.html Mailing List Third Party Advisory
https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html Mailing List Third Party Advisory
https://cert-portal.siemens.com/productcert/html/ssa-032379.html
https://cert-portal.siemens.com/productcert/html/ssa-082556.html
cvelogic Threat Intelligence