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Fencer Intel
medium 6.7

CVE-2020-35506 json

A use-after-free vulnerability was found in the am53c974 SCSI host bus adapter emulation of QEMU in versions before 6.0.0 during the handli…

published 5y ago modified 4mo ago also EUVD-2020-23175

cvss
6.7
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
0.4%
EPSS 0.4% chance of exploitation in 30 days, percentile 30%
public exploits
0
none known

Summary

A use-after-free vulnerability was found in the am53c974 SCSI host bus adapter emulation of QEMU in versions before 6.0.0 during the handling of the 'Information Transfer' command (CMD_TI). This flaw allows a privileged guest user to crash the QEMU process on the host, resulting in a denial of service or potential code execution with the privileges of the QEMU process.

Patch / fix

  • qemu qemu 6.0.0
  • qemu Debian 14, Debian 13, Debian 12 1:6.0+dfsg-3

debian advisories DEBIAN-CVE-2020-35506

  • qemu SLES for SAP 12 SP4, SLES 12 SP4-LTSS, OpenStack Cloud Crowbar 9 +1 more 2.11.2-5.40.2
  • qemu SLES for SAP 15 SP1, SLES 15 SP1-LTSS, SLES 15 SP1-BCL +3 more 3.1.1.1-80.40.1
  • qemu SLES for SAP 15, SLES 15-LTSS, SLE High Performance Computing 15-LTSS +1 more 2.11.2-70.59.1
  • qemu SLES 12 SP2-BCL 2.6.2-41.73.1
  • qemu SLE Module for Server Applications 15 SP3, SLE Module for Basesystem 15 SP3 5.2.0-103.2
  • qemu SLES for SAP 12 SP5, SLES 12 SP5 3.1.1.1-57.2
  • qemu SLE Module for Server Applications 15 SP2, SLE Module for Basesystem 15 SP2, SLE Micro 5.0 4.2.1-11.28.1

suse advisories SUSE-SU-2021:3635-1SUSE-SU-2021:3614-1SUSE-SU-2021:3613-1SUSE-SU-2021:3575-1SUSE-SU-2021:2858-1SUSE-SU-2021:2813-1

  • qemu openSUSE Leap 15.3 3.1.1.1-80.40.1
  • qemu openSUSE Leap 15.3 5.2.0-103.2
  • qemu openSUSE Leap 15.2 4.2.1-lp152.9.20.1
  • qemu-testsuite openSUSE Leap 15.2 4.2.1-lp152.9.20.1
  • qemu-linux-user openSUSE Leap 15.2 4.2.1-lp152.9.20.1
  • qemu openSUSE Leap 15.3 4.2.1-11.28.1

opensuse advisories openSUSE-SU-2021:3614-1openSUSE-SU-2021:2858-1openSUSE-SU-2021:1202-1openSUSE-SU-2021:2789-1

  • qemu Alpine 3.24, Alpine 3.23, Alpine 3.22 +6 more 6.0.0-r2

alpine advisories ALPINE-CVE-2020-35506

Alpine secdb © Alpine Linux, from https://secdb.alpinelinux.org via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

Is CVE-2020-35506 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.

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Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2020-35506 updated cvss 5.0

QEMU: use after free vulnerability in esp_do_dma() in hw/scsi/esp.c

  • Red Hat Enterprise Linux 5 kvm Red Hat Enterprise Linux 6 qemu-img, qemu-kvm, qemu-kvm-tools, qemu-guest-agent, qemu-guest-agent-win32 Red Hat Enterprise Linux 7 qemu-img, qemu-kvm, libcacard, qemu-img-ma, qemu-kvm-ma, qemu-img-rhev, +9 more Red Hat Enterprise Linux 8 qemu-img, qemu-kvm, qemu-kvm-core, qemu-kvm-tests, qemu-kvm-common, qemu-guest-agent, +8 more Red Hat Enterprise Linux 8 Advanced Virtualization qemu-img, qemu-kvm, qemu-kiwi, qemu-kvm-core, qemu-kvm-tests, qemu-kvm-common, +9 more Red Hat Enterprise Linux 9 qemu-img, qemu-kvm, qemu-kvm-core, qemu-kvm-tools, qemu-pr-helper, qemu-kvm-common, +16 more
    +2 more products
    Red Hat OpenStack Platform 10 (Newton) qemu-img-rhev, qemu-kvm-rhev, qemu-kvm-tools-rhev, qemu-kvm-common-rhev Red Hat OpenStack Platform 13 (Queens) qemu-img-rhev, qemu-kvm-rhev, qemu-kvm-tools-rhev, qemu-kvm-common-rhev
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

Exploit prediction

0.37% chance of exploitation in the next 30 days, higher than 30% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by version score vector
NVD 3.1 6.7 CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
NVD 2.0 4.6 AV:L/AC:L/Au:N/C:P/I:P/A:P

Affected products

  • n/a QEMU

Classification

Weakness

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.