#VU33957 Input validation error in Perl - CVE-2011-2939

Vulnerability identifier: #VU33957

Vulnerability risk: Medium

CVSSv4.0: 1.7 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2011-2939

CWE-ID: CWE-20

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Perl
Universal components / Libraries / Scripting languages

Vendor: Perl

Description

The vulnerability allows a remote non-authenticated attacker to read and manipulate data.

Off-by-one error in the decode_xs function in Unicode/Unicode.xs in the Encode module before 2.44, as used in Perl before 5.15.6, might allow context-dependent attackers to cause a denial of service (memory corruption) via a crafted Unicode string, which triggers a heap-based buffer overflow.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Perl: 2.0.0, 2.1.0 - 2.18.1, 2.2.0 - 2.2.2, 2.3.0, 2.4.0, 2.5.0 - 2.5.1, 2.6.0 - 2.6.6, 2.7.0 - 2.7.2, 2.8.0 - 2.8.8, 2.9.0 - 2.9.2

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External links
https://cpansearch.perl.org/src/FLORA/perl-5.14.2/pod/perldelta.pod
https://perl5.git.perl.org/perl.git/commitdiff/e46d973584785af1f445c4dedbee4243419cb860#patch5
https://search.cpan.org/~flora/perl-5.14.2/pod/perldelta.pod#Encode_decode_xs_n-byte_heap-overflow_(CVE-2011-2939)
https://secunia.com/advisories/46172
https://secunia.com/advisories/46989
https://secunia.com/advisories/51457
https://secunia.com/advisories/55314
https://www.mandriva.com/security/advisories?name=MDVSA-2012:008
https://www.openwall.com/lists/oss-security/2011/08/18/8
https://www.openwall.com/lists/oss-security/2011/08/19/17
https://www.redhat.com/support/errata/RHSA-2011-1424.html
https://www.securityfocus.com/bid/49858
https://www.ubuntu.com/usn/USN-1643-1
https://bugzilla.redhat.com/show_bug.cgi?id=731246

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.