VulnerabilityPublished 11 Sep 2026Updated 5 Oct 2026

CVE-2026-89531: Linux kernel · svcrdma: Reject connection when transport allocation fails

Affects Linux kernelSource GCVE Database

Authoritative record:CVE-2026-89531

Not known to be exploited.

Data as of 26 Oct 2026, 14:05 UTC

Severity

Medium

Rated by Threat Radar · CVSS not yet scored by NVD

EPSS: 0.1% chance of exploitation in 30 days – higher than 6% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

Exploitation evidence

Disclosed: evidence found.
CVE published 11 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Affected software

Product	Affected	Fixed in
Ubuntu 26.04 LTSlinux`pkg:deb/ubuntu/linux?arch=source&distro=resolute`Other threats	Affected 6.17.0-5.5 – 7.0.0-38.38 23 affected builds	Fixed in–
Ubuntu 26.04 LTSlinux-aws`pkg:deb/ubuntu/linux-aws?arch=source&distro=resolute`Other threats	Affected 6.17.0-1002.2 – 7.0.0-1014.14 15 affected builds	Fixed in–
Ubuntu 26.04 LTSlinux-azure`pkg:deb/ubuntu/linux-azure?arch=source&distro=resolute`Other threats	Affected 6.17.0-1003.3 – 7.0.0-1017.17 15 affected builds	Fixed in–
Ubuntu 26.04 LTSlinux-azure-fde`pkg:deb/ubuntu/linux-azure-fde?arch=source&distro=resolute`Other threats	Affected 7.0.0-1003.3 – 7.0.0-1016.16 9 affected builds	Fixed in–
Ubuntu 26.04 LTSlinux-gcp`pkg:deb/ubuntu/linux-gcp?arch=source&distro=resolute`Other threats	Affected 6.17.0-1002.2 – 7.0.0-1014.14 13 affected builds	Fixed in–
Ubuntu 26.04 LTSlinux-gke`pkg:deb/ubuntu/linux-gke?arch=source&distro=resolute`Other threats	Affected 7.0.0-1002.3 – 7.0.0-1008.9 6 affected builds	Fixed in–

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

AI-suggested

A fix is available that modifies the CM event handler to reject connections when transport allocation fails, ensuring proper cleanup of resources. Users should apply the official Linux kernel updates that include this fix. Patch status is not explicitly confirmed in the provided data; users should consult the vendor advisory for current remediation guidance.

Description

A vulnerability in the Linux kernel's svcrdma component causes a memory leak when transport allocation fails during connection requests. The issue arises because the connection manager (CM) core returns success without destroying the orphaned rdma_cm_id, leading to resource leaks under memory pressure. This can be amplified by a remote peer repeatedly attempting connections. The vulnerability has been resolved by modifying the CM event handler to reject connections on allocation failure, ensuring proper cleanup.

Impact

The vulnerability causes memory leaks in the Linux kernel's RDMA connection management under memory pressure, potentially leading to resource exhaustion. A remote attacker could exploit this by sending repeated connection attempts, amplifying the leak. There is no indication of code execution or privilege escalation. The impact is primarily denial of service through resource depletion.

Summary

The Linux kernel svcrdma module had a vulnerability where the handle_connect_req() function did not handle failures in svc_rdma_create_xprt() properly. When transport allocation failed, the CM core returned 0 for CONNECT_REQUEST events, preventing destruction of the newly created rdma_cm_id, causing a memory leak. This leak could be exploited by a remote peer to amplify resource exhaustion. The fix involves returning a non-zero status from the CM event handler on allocation failure, prompting the CM core to destroy the orphaned rdma_cm_id and prevent leaks.

References

Community reviews

Loading reviews…

Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 25 Oct 2026, 01:59 UTC

Technical details

References

Community reviews

Related threats