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TI-2020-01899 Aliases CVE-2020-1983GHSA-m3gw-pxj4-v7p8

libslirp: use after free vulnerability cause a denial of service.

Priority LOW 37CWE-416Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Partial Red Hat: 14 fixed, 7 without a fix

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-416 and the CVSS impact.

Summary

A use after free vulnerability in ip_reass() in ip_input.c of libslirp 4.2.0 and prior releases allows crafted packets to cause a denial of service.

Why it matters now

EPSS 0.02357 83rd percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Partial Red Hat: 7 advisoriesRed Hat: 14 fixed, 7 without a fix

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
slirplibslirpup to 4.2.0—No fix listedCNA
  • libslirp Vendorslirp Affected up to 4.2.0 Fixed in — No fix listed CNA

CPE configurations NVD · 10

CPEVersionsRoleVendor
cpe:2.3:a:libslirp_project:libslirp:*:*:*:*:*:*:*:*up to 4.2.0VulnerableLibslirp Project
cpe:2.3:o:fedoraproject:fedora:31:*:*:*:*:*:*:*31VulnerableFedoraproject
cpe:2.3:o:fedoraproject:fedora:32:*:*:*:*:*:*:*32VulnerableFedoraproject
cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*8.0VulnerableDebian
cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*9.0VulnerableDebian
cpe:2.3:o:opensuse:leap:15.1:*:*:*:*:*:*:*15.1VulnerableopenSUSE
cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:esm:*:*:*16.04VulnerableCanonical
cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:*18.04VulnerableCanonical
cpe:2.3:o:canonical:ubuntu_linux:19.10:*:*:*:*:*:*:*19.10VulnerableCanonical
cpe:2.3:o:canonical:ubuntu_linux:20.04:*:*:*:lts:*:*:*20.04VulnerableCanonical
  • cpe:2.3:a:libslirp_project:libslirp:*:*:*:*:*:*:*:* Versions up to 4.2.0 Vulnerable ·Libslirp Project
  • cpe:2.3:o:fedoraproject:fedora:31:*:*:*:*:*:*:* Versions 31 Vulnerable ·Fedoraproject
  • cpe:2.3:o:fedoraproject:fedora:32:*:*:*:*:*:*:* Versions 32 Vulnerable ·Fedoraproject
  • cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:* Versions 8.0 Vulnerable ·Debian
  • cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:* Versions 9.0 Vulnerable ·Debian
  • cpe:2.3:o:opensuse:leap:15.1:*:*:*:*:*:*:* Versions 15.1 Vulnerable ·openSUSE
  • cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:esm:*:*:* Versions 16.04 Vulnerable ·Canonical
  • cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:* Versions 18.04 Vulnerable ·Canonical
  • cpe:2.3:o:canonical:ubuntu_linux:19.10:*:*:*:*:*:*:* Versions 19.10 Vulnerable ·Canonical
  • cpe:2.3:o:canonical:ubuntu_linux:20.04:*:*:*:lts:*:*:* Versions 20.04 Vulnerable ·Canonical

Remediation

Red Hat 7 advisories

  • RHSA-2021:0934 Released 2021-03-18 · Red Hat rating Moderate
    qemu-kvm-rhev security update
    • Red Hat OpenStack Platform 13.0 qemu-img-rhev-10:2.12.0-48.el7_9.2, qemu-kvm-common-rhev-10:2.12.0-48.el7_9.2, qemu-kvm-rhev-10:2.12.0-48.el7_9.2 +1
  • RHSA-2021:0459 Released 2021-02-09 · Red Hat rating Moderate
    qemu-kvm-rhev security update
    • RHV-M 4.3 qemu-img-rhev-10:2.12.0-48.el7_9.2, qemu-kvm-common-rhev-10:2.12.0-48.el7_9.2, qemu-kvm-rhev-10:2.12.0-48.el7_9.2 +1
    • Red Hat Virtualization 4 Management Agent for RHEL 7 Hosts qemu-img-rhev-10:2.12.0-48.el7_9.2, qemu-kvm-common-rhev-10:2.12.0-48.el7_9.2, qemu-kvm-rhev-10:2.12.0-48.el7_9.2 +1
  • RHSA-2021:0346 Released 2021-02-02 · Red Hat rating Moderate
    qemu-kvm-ma security update
    • Red Hat Enterprise Linux Server (v. 7) qemu-img-ma-10:2.12.0-48.el7_9.2, qemu-kvm-common-ma-10:2.12.0-48.el7_9.2, qemu-kvm-ma-10:2.12.0-48.el7_9.2 +1
    • Red Hat Enterprise Linux Server Optional (v. 7) qemu-kvm-common-ma-10:2.12.0-48.el7_9.2, qemu-kvm-ma-10:2.12.0-48.el7_9.2, qemu-kvm-tools-ma-10:2.12.0-48.el7_9.2
Show 4 more Red Hat advisories
  • RHSA-2020:4676 Released 2020-11-04 · Red Hat rating Moderate
    virt:rhel and virt-devel:rhel security, bug fix, and enhancement update
    • Red Hat CodeReady Linux Builder (v. 8) SLOF-20191022-3.git899d9883.module+el8.3.0+6423+e4cb6418.src::virt-devel:rhel, hivex-1.3.18-20.module+el8.3.0+6423+e4cb6418.i686::virt-devel:rhel, hivex-devel-1.3.18-20.module+el8.3.0+6423+e4cb6418.i686::virt-devel:rhel +47
    • Red Hat Enterprise Linux AppStream (v. 8) SLOF-20191022-3.git899d9883.module+el8.3.0+6423+e4cb6418.noarch::virt:rhel, SLOF-20191022-3.git899d9883.module+el8.3.0+6423+e4cb6418.src::virt:rhel, hivex-1.3.18-20.module+el8.3.0+6423+e4cb6418.aarch64::virt:rhel +47
  • RHSA-2020:4290 Released 2020-10-20 · Red Hat rating Important
    virt:8.1 and virt-devel:8.1 security update
    • Advanced Virtualization CodeReady Builder for RHEL 8.1.1 SLOF-20190703-1.gitba1ab360.module+el8.1.1+5309+6d656f05.src::virt-devel:8.1, hivex-1.3.15-7.module+el8.1.1+5309+6d656f05.i686::virt-devel:8.1, hivex-devel-1.3.15-7.module+el8.1.1+5309+6d656f05.i686::virt-devel:8.1 +47
    • Advanced Virtualization for RHEL 8.1.1 SLOF-20190703-1.gitba1ab360.module+el8.1.1+5309+6d656f05.noarch::virt:8.1, SLOF-20190703-1.gitba1ab360.module+el8.1.1+5309+6d656f05.src::virt:8.1, hivex-1.3.15-7.module+el8.1.1+5309+6d656f05.aarch64::virt:8.1 +47
  • RHSA-2020:4079 Released 2020-09-30 · Red Hat rating Important
    qemu-kvm security update
    • Red Hat Enterprise Linux Client (v. 7) qemu-img-10:1.5.3-175.el7_9.1, qemu-kvm-10:1.5.3-175.el7_9.1, qemu-kvm-common-10:1.5.3-175.el7_9.1 +1
    • Red Hat Enterprise Linux ComputeNode Optional (v. 7) qemu-img-10:1.5.3-175.el7_9.1, qemu-kvm-10:1.5.3-175.el7_9.1, qemu-kvm-common-10:1.5.3-175.el7_9.1 +1
    • Red Hat Enterprise Linux Server (v. 7) qemu-img-10:1.5.3-175.el7_9.1, qemu-kvm-10:1.5.3-175.el7_9.1, qemu-kvm-common-10:1.5.3-175.el7_9.1 +1
    • Red Hat Enterprise Linux Workstation (v. 7) qemu-img-10:1.5.3-175.el7_9.1, qemu-kvm-10:1.5.3-175.el7_9.1, qemu-kvm-common-10:1.5.3-175.el7_9.1 +1
  • RHSA-2020:3053 Released 2020-07-21 · Red Hat rating Moderate
    container-tools:rhel8 security, bug fix, and enhancement update
    • Red Hat Enterprise Linux AppStream (v. 8) buildah-1.14.9-1.module+el8.2.1+6689+748e6520.aarch64::container-tools:rhel8, buildah-1.14.9-1.module+el8.2.1+6689+748e6520.ppc64le::container-tools:rhel8, buildah-1.14.9-1.module+el8.2.1+6689+748e6520.s390x::container-tools:rhel8 +47

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux 5AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux 6AffectedNo fix planned: Will not fix
Red Hat Enterprise Linux 7AffectedNo fix planned: Will not fix
Red Hat Enterprise Linux 8AffectedNo fix yet
Red Hat Enterprise Linux 8 Advanced VirtualizationAffectedNo fix yet
Red Hat OpenShift Container Platform 4AffectedNo fix yet
Red Hat OpenStack Platform 10 (Newton)AffectedNo fix planned: Out of support scope
Advanced Virtualization CodeReady Builder for RHEL 8.1.1Fixed RHSA-2020:4290
Advanced Virtualization CodeReady Builder for RHEL 8.2.1Fixed—
Advanced Virtualization for RHEL 8.1.1Fixed RHSA-2020:4290
Advanced Virtualization for RHEL 8.2.1Fixed—
RHV-M 4.3Fixed RHSA-2021:0459
Red Hat CodeReady Linux Builder (v. 8)Fixed RHSA-2020:4676
Red Hat Enterprise Linux AppStream (v. 8)Fixed RHSA-2020:3053, RHSA-2020:4676
Red Hat Enterprise Linux Client (v. 7)Fixed RHSA-2020:4079
Red Hat Enterprise Linux ComputeNode Optional (v. 7)Fixed RHSA-2020:4079
Red Hat Enterprise Linux Server (v. 7)Fixed RHSA-2020:4079, RHSA-2021:0346
Red Hat Enterprise Linux Server Optional (v. 7)Fixed RHSA-2021:0346
Red Hat Enterprise Linux Workstation (v. 7)Fixed RHSA-2020:4079
Red Hat OpenStack Platform 13.0Fixed RHSA-2021:0934
Red Hat Virtualization 4 Management Agent for RHEL 7 HostsFixed RHSA-2021:0459
Not affected: 2 products
  • Red Hat Enterprise Linux 8 Advanced Virtualization
  • Red Hat Enterprise Linux 9

Timeline

  1. 2026-10-02 Threatist record created from CVE-2020-1983
  2. 2026-10-03 Alias added: GHSA-m3gw-pxj4-v7p8

References

Exploit 1

Patch 1

Advisory 8

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences