CVE-2026-120830: libslirp · Out-of-bounds Read
Source GCVE Database
Not known to be exploited · CVSS 7.4 High.
Data as of 3 Nov 2026, 01:29 UTC
Thin evidence
One scorer or none| CNA (redhat) | CVSS 3.1 | 7.4 |
|---|
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:NExploitation evidence
Disclosed: evidence found.
CVE published 3 Nov 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: 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 2 Nov 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Red Hat Enterprise Linux 10libslirp | Affected– | Fixed in– |
| Red Hat Enterprise Linux 8container-tools:rhel8/libslirp | Affected– | Fixed in– |
| Red Hat Enterprise Linux 9libslirp | Affected– | Fixed in– |
| Red Hat OpenShift Container Platform 4libslirp | Affected– | Fixed in– |
| Red Hat OpenShift Container Platform 4openshift/ose-rhel-coreos-8 | Affected– | Fixed in– |
| Red Hat OpenShift Container Platform 4openshift/ose-rhel-coreos-9 | Affected– | Fixed in– |
AI-suggested
Red Hat currently does not have a practical temporary workaround that fully mitigates this issue. Customers are advised to apply relevant security updates when they become available. Monitoring Red Hat advisories for patch releases is recommended.
Description
A vulnerability in libslirp's icmp_forward_error() function allows an out-of-bounds heap read when constructing ICMP error responses. The flaw arises because the length of the quoted original IPv4 packet is taken from the IP header without verifying it against the actual buffer length. This can lead to leakage of host memory into ICMP error packets sent to guests or containers.
References
- nvd.nist.gov/vuln/detail/CVE-2026-120830 (opens in a new tab)
- access.redhat.com/security/cve/CVE-2026-120830 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2565424 (opens in a new tab)
- gitlab.freedesktop.org/slirp/libslirp/-/commit/21b33a6c5588af9f58d15e528fdc1019452708e4 (opens in a new tab)