#1016212 squirrel3: CVE-2021-41556

Package:
src:squirrel3
Source:
src:squirrel3
Submitter:
Moritz Mühlenhoff
Date:
2026-06-25 20:35:02 UTC
Severity:
normal
Tags:
#1016212#5
Date:
2022-07-29 14:36:34 UTC
From:
To:
Hi,

The following vulnerability was published for squirrel3.

CVE-2021-41556[0]:
| sqclass.cpp in Squirrel through 2.2.5 and 3.x through 3.1 allows an
| out-of-bounds read (in the core interpreter) that can lead to Code
| Execution. If a victim executes an attacker-controlled squirrel
| script, it is possible for the attacker to break out of the squirrel
| script sandbox even if all dangerous functionality such as File System
| functions has been disabled. An attacker might abuse this bug to
| target (for example) Cloud services that allow customization via
| SquirrelScripts, or distribute malware through video games that embed
| a Squirrel Engine.

https://github.com/albertodemichelis/squirrel/commit/23a0620658714b996d20da3d4dd1a0dcf9b0bd98
https://blog.sonarsource.com/squirrel-vm-sandbox-escape/

If you fix the vulnerability please also make sure to include the
CVE (Common Vulnerabilities & Exposures) id in your changelog entry.

For further information see:

[0] https://security-tracker.debian.org/tracker/CVE-2021-41556
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-41556

Please adjust the affected versions in the BTS as needed.

#1016212#16
Date:
2026-06-15 14:28:13 UTC
From:
To:
Dear maintainer,

I've prepared an NMU for squirrel3 (versioned as 3.1-8.5) and uploaded
it to DELAYED/2. Please feel free to tell me if I should cancel it.

cu
Adrian

#1016212#25
Date:
2026-06-17 11:35:58 UTC
From:
To:
We believe that the bug you reported is fixed in the latest version of
squirrel3, which is due to be installed in the Debian FTP archive.

A summary of the changes between this version and the previous one is
attached.

Thank you for reporting the bug, which will now be closed.  If you
have further comments please address them to 1016212@bugs.debian.org,
and the maintainer will reopen the bug report if appropriate.

Debian distribution maintenance software
pp.
Adrian Bunk <bunk@debian.org> (supplier of updated squirrel3 package)

(This message was generated automatically at their request; if you
believe that there is a problem with it please contact the archive
administrators by mailing ftpmaster@ftp-master.debian.org)
Format: 1.8
Date: Mon, 15 Jun 2026 17:22:20 +0300
Source: squirrel3
Architecture: source
Version: 3.1-8.5
Distribution: unstable
Urgency: medium
Maintainer: Fabian Wolff <fabi.wolff@arcor.de>
Changed-By: Adrian Bunk <bunk@debian.org>
Closes: 1016212
Changes:
 squirrel3 (3.1-8.5) unstable; urgency=medium
 .
   * Non-maintainer upload.
   * CVE-2021-41556: Sandbox Escape (Closes: #1016212)
Checksums-Sha1:
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 d6ab41ba6ef35d331f8583b2c053815429a9f20a 8084 squirrel3_3.1-8.5.debian.tar.xz
Checksums-Sha256:
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 f9bda63c3a355f259cab958d3e0e93e11bead4ac9938f8e9c131fd856bedcd71 8084 squirrel3_3.1-8.5.debian.tar.xz
Files:
 8209338c2fd0d254bf24a747619f46c1 2043 interpreters optional squirrel3_3.1-8.5.dsc
 22163eb81d2cebd27e6aac9daa1edaef 8084 interpreters optional squirrel3_3.1-8.5.debian.tar.xz
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#1016212#30
Date:
2026-06-25 20:32:06 UTC
From:
To:
We believe that the bug you reported is fixed in the latest version of
squirrel3, which is due to be installed in the Debian FTP archive.

A summary of the changes between this version and the previous one is
attached.

Thank you for reporting the bug, which will now be closed.  If you
have further comments please address them to 1016212@bugs.debian.org,
and the maintainer will reopen the bug report if appropriate.

Debian distribution maintenance software
pp.
Adrian Bunk <bunk@debian.org> (supplier of updated squirrel3 package)

(This message was generated automatically at their request; if you
believe that there is a problem with it please contact the archive
administrators by mailing ftpmaster@ftp-master.debian.org)
Format: 1.8
Date: Thu, 18 Jun 2026 23:28:11 +0300
Source: squirrel3
Architecture: source
Version: 3.1-8.2+deb13u1
Distribution: trixie
Urgency: medium
Maintainer: Fabian Wolff <fabi.wolff@arcor.de>
Changed-By: Adrian Bunk <bunk@debian.org>
Closes: 1016212
Changes:
 squirrel3 (3.1-8.2+deb13u1) trixie; urgency=medium
 .
   * Non-maintainer upload.
   * CVE-2021-41556: Sandbox Escape (Closes: #1016212)
Checksums-Sha1:
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 16d4636348dd50c9ee3c859a113553157da97a84 175612 squirrel3_3.1.orig.tar.gz
 c1f9bf4b21e2285f00f15eebb2d2de90226dce26 7840 squirrel3_3.1-8.2+deb13u1.debian.tar.xz
Checksums-Sha256:
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Files:
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 2f8350d4d1c524a89b360ee3f8f8066b 175612 interpreters optional squirrel3_3.1.orig.tar.gz
 c14a1f847f48ccaa1235e75c3ff91ef5 7840 interpreters optional squirrel3_3.1-8.2+deb13u1.debian.tar.xz
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