CVE-2021-3595: Low severity Libslirp Project Libslirp vulnerability

Published Jun 10, 2021
·
Updated

An invalid pointer initialization issue was found in the SLiRP networking implementation of QEMU. The flaw exists in the tftpinput() function and could occur while processing a udp packet that is smaller than the size of the 'tftpt' structure. This issue may lead to out-of-bounds read access or indirect host memory disclosure to the guest. The highest threat from this vulnerability is to data confidentiality.

Other sources

An invalid pointer initialization issue was found in the SLiRP networking implementation of QEMU. The function tftpinput() handles requests for the tftp protocol from the guest. While processing a udp packet that is smaller than the size of the tftpt structure it uses memory from outside the working mbuf buffer. This issue may lead to out of bound read access or indirect memory disclosure to the guest.

Upstream commits: https://gitlab.freedesktop.org/slirp/libslirp/-/commit/93e645e7 https://gitlab.freedesktop.org/slirp/libslirp/-/commit/3f179481 https://gitlab.freedesktop.org/slirp/libslirp/-/commit/990163cf

Red Hat

Affected Software

9 affected componentsFixes available
redhat/libslirp<4.6.0
4.6.0
Libslirp Project Libslirp<4.6.0
redhat Enterprise Linux=8.0
redhat Enterprise Linux=8.0
Debian Debian Linux=9.0
Fedoraproject Fedora=33
Fedoraproject Fedora=34
debian/libslirp
4.4.0-1+deb11u24.7.0-14.8.0-1
debian/qemu
1:5.2+dfsg-11+deb11u31:5.2+dfsg-11+deb11u21:7.2+dfsg-7+deb12u121:10.0.0~rc2+ds-21:10.0.0~rc3+ds-2

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade redhat/libslirp to a version that resolves this vulnerability.

    Fixed in 4.6.0
  2. Upgrade

    Upgrade debian/libslirp to a version that resolves this vulnerability.

    Fixed in 4.4.0-1+deb11u2Fixed in 4.7.0-1Fixed in 4.8.0-1
  3. Upgrade

    Upgrade debian/qemu to a version that resolves this vulnerability.

    Fixed in 1:5.2+dfsg-11+deb11u3Fixed in 1:5.2+dfsg-11+deb11u2Fixed in 1:7.2+dfsg-7+deb12u12Fixed in 1:10.0.0~rc2+ds-2Fixed in 1:10.0.0~rc3+ds-2
  4. Upgrade

    Upgrade libslirp to a version that resolves this vulnerability.

    Fixed in 4.6.0Patch commit/3f179481
  5. Upgrade

    Upgrade libslirp to a version that resolves this vulnerability.

    Fixed in 4.6.0Patch commit/93e645e7
  6. Upgrade

    Upgrade libslirp to a version that resolves this vulnerability.

    Fixed in 4.6.0Patch commit/990163cf

Event History

Jun 14, 2021
CVE Published
12:00 AM
Data Sourced
12:00 AM
RemedyDescriptionSeverityWeaknessAffected Software
Jun 15, 2021
CVE Published
via MITRE·12:00 AM
Data Sourced
via MITRE·12:00 AM
DescriptionWeakness
Data Sourced
via NVD·09:15 PM
RemedyDescriptionSeverityWeaknessAffected Software
Jan 11, 2024
Data Sourced
via Launchpad·11:57 PM
Description
Sep 16, 2024
Data Sourced
via Ubuntu·02:33 AM
RemedyDescriptionSeverityAffected Software

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is the vulnerability ID for this issue?

The vulnerability ID for this issue is CVE-2021-3595.

2

What is the severity of CVE-2021-3595?

CVE-2021-3595 has a severity level of 3.8 (low).

3

Which software is affected by CVE-2021-3595?

The affected software includes libslirp versions up to and including 4.6.0, Red Hat Enterprise Linux 8.0, Debian Debian Linux 9.0, Fedora 33 and 34.

4

How can I fix CVE-2021-3595?

To fix CVE-2021-3595, it is recommended to update to libslirp version 4.6.1 or newer.

5

Where can I find more information about CVE-2021-3595?

More information about CVE-2021-3595 can be found at the following references: [link1](https://gitlab.freedesktop.org/slirp/libslirp/-/commit/93e645e7), [link2](https://gitlab.freedesktop.org/slirp/libslirp/-/commit/3f179481), [link3](https://gitlab.freedesktop.org/slirp/libslirp/-/commit/990163cf).

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