← Vulnerability feed

Vulnerability record · CVE-2011-2939 · published 13 January 2012

CVE-2011-2939: Dan kogai encode module vulnerability

DDan Kogai · Encode Module

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.

5.1 CVSS 2.0 Medium EPSS 2.6% · top 15.4% CWE-189 · CWE-189
5.1CVSS 2.0 base score
2.6%EPSS exploitation probability, 30 days
NoNot in CISA KEV
2Affected product versions listed by NVD
28References, 2 tagged exploit
16 Jun 2026Last modified by NVD

Description

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.

AV:N/AC:H/Au:N/C:P/I:P/A:P

Affected products

2 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
http://cpansearch.perl.org/src/FLORA/perl-5.14.2/pod/perldelta.pod
http://perl5.git.perl.org/perl.git/commitdiff/e46d973584785af1f445c4dedbee4243419cb860#patch5 ExploitPatch
http://search.cpan.org/~flora/perl-5.14.2/pod/perldelta.pod#Encode_decode_xs_n-byte_heap-overflow_%28CVE-2011-2939%29
http://secunia.com/advisories/46172
http://secunia.com/advisories/46989
http://secunia.com/advisories/51457
http://secunia.com/advisories/55314
http://www.mandriva.com/security/advisories?name=MDVSA-2012:008
http://www.openwall.com/lists/oss-security/2011/08/18/8
http://www.openwall.com/lists/oss-security/2011/08/19/17 Patch
http://www.redhat.com/support/errata/RHSA-2011-1424.html
http://www.securityfocus.com/bid/49858
http://www.ubuntu.com/usn/USN-1643-1
https://bugzilla.redhat.com/show_bug.cgi?id=731246 Patch
http://cpansearch.perl.org/src/FLORA/perl-5.14.2/pod/perldelta.pod
http://perl5.git.perl.org/perl.git/commitdiff/e46d973584785af1f445c4dedbee4243419cb860#patch5 ExploitPatch
http://search.cpan.org/~flora/perl-5.14.2/pod/perldelta.pod#Encode_decode_xs_n-byte_heap-overflow_%28CVE-2011-2939%29
http://secunia.com/advisories/46172
http://secunia.com/advisories/46989
http://secunia.com/advisories/51457
http://secunia.com/advisories/55314
http://www.mandriva.com/security/advisories?name=MDVSA-2012:008
http://www.openwall.com/lists/oss-security/2011/08/18/8
http://www.openwall.com/lists/oss-security/2011/08/19/17 Patch
http://www.redhat.com/support/errata/RHSA-2011-1424.html
http://www.securityfocus.com/bid/49858
http://www.ubuntu.com/usn/USN-1643-1
https://bugzilla.redhat.com/show_bug.cgi?id=731246 Patch

Track CVE-2011-2939 inside VULONE

Watch it alongside the ransomware crews, C2 infrastructure and forum chatter that reference it, query it through the API and pull it into your SIEM over TAXII.

Start free Open in platform

Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

9.8CVE-2026-8376Perl vulnerabilityPerl versions before 5.40.5-RC1, from 5.41.0 before 5.42.3-RC1, from 5.43.0 before 5.43.11 have a heap buffer overflow when compiling regular express…EPSS 0.48%9.8CVE-2026-4176Perl vulnerabilityPerl versions from 5.9.4 before 5.40.4-RC1, from 5.41.0 before 5.42.2-RC1, from 5.43.0 before 5.43.9 contain a vulnerable version of Compress::Raw::Z…EPSS 0.81%9.8CVE-2022-48522Perl out-of-bounds write vulnerabilityIn Perl 5.34.0, function S_find_uninit_var in sv.c has a stack-based crash that can lead to remote code execution or local privilege escalation.EPSS 2.6%9.8CVE-2018-18311Perl integer overflow vulnerabilityPerl before 5.26.3 and 5.28.x before 5.28.1 has a buffer overflow via a crafted regular expression that triggers invalid write operations.EPSS 12%9.8CVE-2018-18314Perl memory buffer overflow vulnerabilityPerl before 5.26.3 has a buffer overflow via a crafted regular expression that triggers invalid write operations.EPSS 6.1%9.8CVE-2018-18312Perl memory buffer overflow vulnerabilityPerl before 5.26.3 and 5.28.0 before 5.28.1 has a buffer overflow via a crafted regular expression that triggers invalid write operations.EPSS 13%9.8CVE-2018-6797Debian linux out-of-bounds write vulnerabilityAn issue was discovered in Perl 5.18 through 5.26. A crafted regular expression can cause a heap-based buffer overflow, with control over the bytes w…EPSS 6.5%9.8CVE-2018-6913Debian linux out-of-bounds write vulnerabilityHeap-based buffer overflow in the pack function in Perl before 5.26.2 allows context-dependent attackers to execute arbitrary code via a large item c…EPSS 11%

Source: NIST National Vulnerability Database (record CVE-2011-2939), CISA KEV, FIRST EPSS (scores of 2026-10-10). This page is refreshed as NVD updates the record.