CVE-2026-89984

UNRATEDCVSS · not yet scoredTrending — 4 sources updated this week
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EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • No CVSS published and no exploitation signals yet
CISA-KEV: Not listedEPSS PROB: 0.2%CVSS v2: —Exploit: None knownExposed services: Not assessed

No fix is confirmed yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for the fix.

In the Linux kernel, the following vulnerability has been resolved:

perf/x86/intel: Fix kernel address leakages in LBR stack

Before Arch LBR gained CPL filtering support, a user-only branch stack could still contain kernel addresses. As a result, kernel branch records may be exposed to user space even when PERF_SAMPLE_BRANCH_USER is requested.

For example, on Intel Tiger Lake, the following command can still report SYSRET/ERET entries with kernel-space from addresses:

$ ./perf record -e cycles:p -o - --branch-filter any,save_type,u -- \ ./perf bench syscall basic --loop 1000 | \ ./perf script -i - --fields brstack|tr ' ' '\n'| \ grep -E '0x[89a-f][0-9a-f]{15}'

Total time: 0.000 [sec]

0.219000 usecs/op 4,566,210 ops/sec [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.551 MB - ] 0xffffffff93c001c8/0x7f12a2b1d647/P/-/-/16959/SYSRET/- 0xffffffff93c001c8/0x7f12a2b1d5c2/P/-/-/17535/SYSRET/- 0xffffffff93c01928/0x7f12a2861000/P/-/-/6719/ERET/- 0xffffffff93c01928/0x7f12a297a000/P/-/-/8575/ERET/-

The problem is that intel_pmu_lbr_filter() does not fully validate the privilege level of sampled entries. It filters some mismatches based on the branch type and the to address, but it does not reject entries whose from address violates the requested branch privilege filter.

Fix this by extending software filtering to validate both from and to addresses against br_sel. Any LBR entry contains kernel address does not match the requested user filter is dropped. This prevents kernel addresses from appearing in user-only branch stacks.

CVSS v3
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EchelonGraph score
Not yet assessedNo source has published severity data for this CVE yet — no CVSS score from NVD or a CNA, no GitHub advisory, and it is not in CISA KEV. This is not a rating of zero; we cannot assess it yet.
EG Score
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EG Risk
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EPSS PROB
0.2%
EPSS %ILE
10th
KEV
Not listed

Published

September 16, 2026

Last Modified

September 16, 2026

References (8)

Vendor Advisories for CVE-2026-89984(2)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Affected Packages

(4 across 3 ecosystems)
Debian:12(2)
PackageVulnerable rangeFix by version rangeDependents
linux6.1.106-1 ... 7.2~rc7-1~exp1 (360 versions)
  • every version on: no fix on record
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linux-6.126.12.100-1~deb12u1, 6.12.101-1~deb12u1, 6.12.107-1~deb12u1
  • every version up to 6.12.111-1~deb12u1: fixed in 6.12.111-1~deb12u1
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Debian:13(1)
PackageVulnerable rangeFix by version rangeDependents
linux6.12.100-1 ... 6.12.96-1 (35 versions)
  • every version up to 6.12.111-1: fixed in 6.12.111-1
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Debian:14(1)
PackageVulnerable rangeFix by version rangeDependents
linux6.12.100-1 ... 7.2~rc7-1~exp1 (179 versions)
  • every version up to 7.2.6-1: fixed in 7.2.6-1
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Data Freshness Timeline

(refreshed 12× in last 7d / 31× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-10-05 05:20 UTCVendor advisory
  2. 2026-10-05 05:20 UTCGHSA enrichment
  3. 2026-10-04 23:22 UTCEPSS rescore
  4. 2026-10-02 02:27 UTCVendor advisory
  5. 2026-10-02 02:26 UTCGHSA enrichment
  6. 2026-10-01 19:51 UTCEPSS rescore
  7. 2026-09-30 15:04 UTCEPSS rescore
  8. 2026-09-28 23:22 UTCEG score recompute
  9. 2026-09-28 23:22 UTCVendor advisory
  10. 2026-09-28 23:22 UTCGHSA enrichment
  11. 2026-09-28 13:52 UTCEPSS rescore
  12. 2026-09-28 13:52 UTCEPSS rescore
  13. 2026-09-27 13:49 UTCEPSS rescore
  14. 2026-09-26 15:59 UTCEPSS rescore
  15. 2026-09-25 20:29 UTCVendor advisory
  16. 2026-09-25 20:29 UTCGHSA enrichment
  17. 2026-09-24 14:04 UTCEPSS rescore
  18. 2026-09-23 17:54 UTCEPSS rescore
  19. 2026-09-22 17:07 UTCVendor advisory
  20. 2026-09-22 17:07 UTCGHSA enrichment
  21. 2026-09-22 16:01 UTCEPSS rescore
  22. 2026-09-21 21:09 UTCEPSS rescore
  23. 2026-09-20 20:16 UTCEPSS rescore
  24. 2026-09-19 14:14 UTCEG score recompute
  25. 2026-09-19 14:14 UTCVendor advisory
Show 6 more
  1. 2026-09-19 14:14 UTCGHSA enrichment
  2. 2026-09-18 19:28 UTCEPSS rescore
  3. 2026-09-17 19:32 UTCEPSS rescore
  4. 2026-09-16 11:21 UTCNVD update
  5. 2026-09-16 10:38 UTCEG score recompute
  6. 2026-09-16 10:36 UTCMITRE cvelistV5first tracked

Frequently asked(4)

What is CVE-2026-89984?
CVE-2026-89984 is a publicly disclosed vulnerability published on September 16, 2026. In the Linux kernel, the following vulnerability has been resolved: perf/x86/intel: Fix kernel address leakages in LBR stack Before Arch LBR gained CPL filtering support, a user-only branch stack could still contain kernel addresses. As a result, kernel branch records may be exposed to user space…
When was CVE-2026-89984 disclosed?
CVE-2026-89984 was first published on September 16, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-89984 actively exploited?
CVE-2026-89984 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.2% probability of exploitation in the next 30 days (10th percentile of EPSS-scored CVEs).
How do I remediate CVE-2026-89984?
No fix for CVE-2026-89984 is confirmed yet. Until one is published, restrict network exposure of the affected system or apply the vendor's mitigation — for example, keep it off the internet or limit it to trusted networks — and watch the vendor's advisory for the fix. The vendor advisories EchelonGraph has for CVE-2026-89984 are linked in the Vendor Advisories panel on this page.

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