November 13, 2026 Follow Egret
CVE-2026-120831 · CVE record: PUBLISHED

Libslirp: libslirp: queue pointer corruption in if_output() leading to denial of service

Red Hat Red Hat Enterprise Linux 10, Red Hat Red Hat Enterprise Linux 8, Red Hat Red Hat Enterprise Linux 9, Red Hat Red Hat OpenShift Container Platform 4, Red Hat Red Hat OpenShift Container Platform 5

A flaw was found in libslirp in if_output(). When moving a session from the fast queue to the batch queue, the code unlinked and reinserted an arbitrary packet via ifm->m_nextpkt instead of the session queue head, corrupting queue pointers. A guest generating burst traffic could crash the host networking process, causing a denial of service.

Exploitation evidence

Not listed in the latest downloaded CISA KEV catalog. This does not establish an absence of exploitation.

KEV checked 13 Nov 2026, 00:20 Jerusalem · Original catalog ↗

Reported products and versions

Red Hat / Red Hat Enterprise Linux 10

Default status: affected

Red Hat / Red Hat Enterprise Linux 8

Default status: affected

Red Hat / Red Hat Enterprise Linux 9

Default status: affected

Red Hat / Red Hat OpenShift Container Platform 4

Default status: affected

Red Hat / Red Hat OpenShift Container Platform 4

Default status: affected

Red Hat / Red Hat OpenShift Container Platform 4

Default status: affected

Red Hat / Red Hat OpenShift Container Platform 5

Default status: affected

Fixes and workarounds

No explicit solution text in the downloaded CVE record. Consult the vendor advisory; unaffected version ranges are shown above as reported, not inferred as a patch recommendation.

Reported workarounds: Red Hat is not aware of a practical temporary workaround that fully mitigates this issue or meets Red Hat Product Security's standards for usability, deployment, applicability, or stability. Customers are advised to apply the relevant security updates when/if they become available.

Sources and related reporting

CVE Program record ↗ · Download tracked evidence as JSON

Monitored source mentions

Shared CVE identifiers link source mentions; they do not establish that the reports describe the same incident.

Observed change timeline

History begins when Egret first downloads each source. It is not the complete upstream CVE history.

12 Nov 2026, 18:20 Jerusalem · EPSS observation updated

Stored EPSS snapshot at this observation.

{
  "date": "2026-11-12",
  "epss": 0.00265,
  "percentile": 0.18627
}
11 Nov 2026, 12:20 Jerusalem · EPSS observation updated

Stored EPSS snapshot at this observation.

{
  "date": "2026-11-10",
  "epss": 0.00265,
  "percentile": 0.18576
}
11 Nov 2026, 12:20 Jerusalem · CVE Program record changed

Stored CNA snapshot at this observation.

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