CVE-2025-39763 — ACPI: APEI: send SIGBUS to current task if synchronous memory error not recovered
In the Linux kernel, the following vulnerability has been resolved: ACPI: APEI: send SIGBUS to current task if synchronous memory error not recovered If a synchronous error is detected as a result of user-space process triggering a 2-bit uncorrected error, the CPU will take a synchronous error exception such as Synchronous External Abort (SEA) on Arm64. The kernel will queue a memory_failure() work which poisons the related page, unmaps the page, and then sends a SIGBUS to the process, so that a system wide panic can be avoided. However, no memory_failure() work will be queued when abnormal synchronous errors occur. These errors can include situations like invalid PA, unexpected severity, no memory failure config support, invalid GUID section, etc. In such a case, the user-space process will trigger SEA again. This loop can potentially exceed the platform firmware threshold or even trigger a kernel hard lockup, leading to a system reboot. Fix it by performing a force kill if no memory_failure() work is queued for synchronous errors. [ rjw: Changelog edits ]
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)+1
- Technical severity (medium)+3
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.
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
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, Linux Linux Kernel).
- Apply the fixed version or the patch documented under Remediation.
- 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 |
≥ 8fcc4ae6faf8b455eeef00bc9ae70744e3b0f462 and < 2fbc85da9ac9386bd89fcc94e0aadaea19d47784≥ 8fcc4ae6faf8b455eeef00bc9ae70744e3b0f462 and < 082735fbcdb6cd0cf20fbec94516ab2996f1cdd5≥ 8fcc4ae6faf8b455eeef00bc9ae70744e3b0f462 and < cfc9bc15bda6fd0c496cbe2c628564d4d7c332c1≥ 8fcc4ae6faf8b455eeef00bc9ae70744e3b0f462 and < af089e41811a1ad6a7b2b80e839a73ec4c3cecdd≥ 8fcc4ae6faf8b455eeef00bc9ae70744e3b0f462 and < 3cb4f18797247985b0f51d5300f8cb6c78f343ea≥ 8fcc4ae6faf8b455eeef00bc9ae70744e3b0f462 and < 79a5ae3c4c5eb7e38e0ebe4d6bf602d296080060version af02933d59bd1621a48d8b0b331cca9e530ba14b≥ 5.4.69 and < 5.5 and 1 moreversion 5.8 |
Vulnerable | CVE Program (cve.org) e CISA ADP |
| Linux | Linux Kernel | < 6.6.103≥ 6.7 and < 6.12.43≥ 6.13 and < 6.15.11≥ 6.16 and < 6.16.2 | Vulnerable | NIST National Vulnerability Database |
Attack characteristics
The CVSS vector, decoded. It describes the attack, not your exposure to it.
Every base score collected
Sources score independently and may disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Scored by |
|---|---|---|---|---|---|
| 5.5 | CVSS 3.1 | Medium | 1.8 | 3.6 | nvd@nist.gov via NIST National Vulnerability Database |
| 5.5 | CVSS 3.1 | Medium | — | — | GitHub, Inc. via GitHub Security Advisories |
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H (score shown at the top: nvd@nist.gov) Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Local/physical vector: focus on endpoint telemetry (EDR) from affected hosts.
Timeline
What happened to this CVE, newest first.
- 2026
- Fix documented
- Affected products added · linux/linux kernel
- CVSS changed · 5.5
- Source status changed · Published → Analyzed
- Record published
- Affected products added · linux/linux
- Source status changed · → Published
- Record created in this database
- 2025
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 2× References added · Oct 19, 2026 – Oct 19, 2026
- 1× Official description updated · Oct 19, 2026 – Oct 19, 2026
References
8 on the record
- git.kernel.org/stable/c/3cb4f18797247985b0f51d5300f8cb6c78f343ea
- git.kernel.org/stable/c/2fbc85da9ac9386bd89fcc94e0aadaea19d47784
- git.kernel.org/stable/c/79a5ae3c4c5eb7e38e0ebe4d6bf602d296080060
- git.kernel.org/stable/c/082735fbcdb6cd0cf20fbec94516ab2996f1cdd5
- git.kernel.org/stable/c/af089e41811a1ad6a7b2b80e839a73ec4c3cecdd
- git.kernel.org/stable/c/cfc9bc15bda6fd0c496cbe2c628564d4d7c332c1
- nvd.nist.gov/vuln/detail/CVE-2025-39763
- github.com/advisories/GHSA-g7f2-49vp-j5f7
Elsewhere on this site
Related CVEs (same products)
- Unknown CVE-2026-98866 sched/cache: Introduce task_struct->sched_cache_grp to fix UAF 1d
- Unknown CVE-2026-98867 dm-pcache: bound the logical key offset from persistent memory 1d
- Unknown CVE-2026-98868 dm-pcache: reject a kset that overruns its segment 1d
- Unknown CVE-2026-98856 kprobes: Skip disarmed probes when checking optkprobe overlap 1d
- Unknown CVE-2026-98857 ipvs: bound LBLCR and LBLC cache growth 1d
- Unknown CVE-2026-98858 io_uring: fix task_work add use-after-free with SQPOLL 1d
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 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-2025-39763 is "ACPI: APEI: send SIGBUS to current task if synchronous memory error not recovered", rated Medium. It affects Linux (Linux); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 5.5 describes technical severity. EPSS 0.16% 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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