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.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | libencode-perl | 2.44-1 | — |
| Debian 14 | perl | 5.12.4-4 | — |
| Debian 13 | libencode-perl | 2.44-1 | — |
| Debian 13 | perl | 5.12.4-4 | — |
| Debian 12 | libencode-perl | 2.44-1 | — |
| Debian 12 | perl | 5.12.4-4 | — |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 6 | perl +3 | 4:5.10.1-119.el6_1.1 | RHSA-2011:1424 |
| RHEL 6 | perl-Archive-Extract | 1:0.38-119.el6_1.1 | RHSA-2011:1424 |
| RHEL 6 | perl-Archive-Tar | 1.58-119.el6_1.1 | RHSA-2011:1424 |
| RHEL 6 | perl-CGI | 3.51-119.el6_1.1 | RHSA-2011:1424 |
| RHEL 6 | perl-CPAN | 1.9402-119.el6_1.1 | RHSA-2011:1424 |
| RHEL 6 | perl-CPANPLUS | 0.88-119.el6_1.1 | RHSA-2011:1424 |
| RHEL 6 | perl-Compress-Raw-Zlib | 2.023-119.el6_1.1 | RHSA-2011:1424 |
| RHEL 6 | perl-Compress-Zlib +2 | 2.020-119.el6_1.1 | RHSA-2011:1424 |
| RHEL 6 | perl-Digest-SHA | 1:5.47-119.el6_1.1 | RHSA-2011:1424 |
| RHEL 6 | perl-ExtUtils-CBuilder | 1:0.27-119.el6_1.1 | RHSA-2011:1424 |
| RHEL 6 | perl-ExtUtils-Embed | 1.28-119.el6_1.1 | RHSA-2011:1424 |
| RHEL 6 | perl-ExtUtils-MakeMaker | 6.55-119.el6_1.1 | RHSA-2011:1424 |
| RHEL 6 | perl-ExtUtils-ParseXS | 1:2.2003.0-119.el6_1.1 | RHSA-2011:1424 |
| RHEL 6 | perl-File-Fetch | 0.26-119.el6_1.1 | RHSA-2011:1424 |
| RHEL 6 | perl-IO-Zlib | 1:1.09-119.el6_1.1 | RHSA-2011:1424 |
| RHEL 6 | perl-IPC-Cmd | 1:0.56-119.el6_1.1 | RHSA-2011:1424 |
| RHEL 6 | perl-Locale-Maketext-Simple | 1:0.18-119.el6_1.1 | RHSA-2011:1424 |
| RHEL 6 | perl-Log-Message +2 | 1:0.02-119.el6_1.1 | RHSA-2011:1424 |
| RHEL 6 | perl-Log-Message-Simple | 0.04-119.el6_1.1 | RHSA-2011:1424 |
| RHEL 6 | perl-Module-Build | 1:0.3500-119.el6_1.1 | RHSA-2011:1424 |
| RHEL 6 | perl-Module-CoreList | 2.18-119.el6_1.1 | RHSA-2011:1424 |
| RHEL 6 | perl-Module-Load | 1:0.16-119.el6_1.1 | RHSA-2011:1424 |
| RHEL 6 | perl-Module-Load-Conditional | 0.30-119.el6_1.1 | RHSA-2011:1424 |
| RHEL 6 | perl-Module-Pluggable | 1:3.90-119.el6_1.1 | RHSA-2011:1424 |
| RHEL 6 | perl-Object-Accessor | 1:0.34-119.el6_1.1 | RHSA-2011:1424 |
| RHEL 6 | perl-Params-Check | 1:0.26-119.el6_1.1 | RHSA-2011:1424 |
| RHEL 6 | perl-Parse-CPAN-Meta | 1:1.40-119.el6_1.1 | RHSA-2011:1424 |
| RHEL 6 | perl-Pod-Escapes | 1:1.04-119.el6_1.1 | RHSA-2011:1424 |
| RHEL 6 | perl-Pod-Simple | 1:3.13-119.el6_1.1 | RHSA-2011:1424 |
| RHEL 6 | perl-Term-UI | 0.20-119.el6_1.1 | RHSA-2011:1424 |
| RHEL 6 | perl-Test-Harness | 3.17-119.el6_1.1 | RHSA-2011:1424 |
| RHEL 6 | perl-Test-Simple | 0.92-119.el6_1.1 | RHSA-2011:1424 |
| RHEL 6 | perl-Time-HiRes | 4:1.9721-119.el6_1.1 | RHSA-2011:1424 |
| RHEL 6 | perl-Time-Piece | 1.15-119.el6_1.1 | RHSA-2011:1424 |
| RHEL 6 | perl-core | 5.10.1-119.el6_1.1 | RHSA-2011:1424 |
| RHEL 6 | perl-parent | 1:0.221-119.el6_1.1 | RHSA-2011:1424 |
| RHEL 6 | perl-version | 3:0.77-119.el6_1.1 | RHSA-2011:1424 |
Advisories 1
- RHSA-2011:1424 Red Hat Security Advisory: perl security update Red Hat Security Advisories (RHSA) · Jan 29, 2026
References
- 46989 third-party-advisory
- http://cpansearch.perl.org/src/FLORA/perl-5.14.2/pod/perldelta.pod
- 55314 third-party-advisory
- USN-1643-1 vendor-advisory
- 49858 vdb-entry
- [oss-security] 20110818 CVE request: heap overflow in perl while decoding Unicode string mailing-list
- http://perl5.git.perl.org/perl.git/commitdiff/e46d973584785af1f445c4dedbee4243419cb860#patch5
- 46172 third-party-advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=731246
- http://search.cpan.org/~flora/perl-5.14.2/pod/perldelta.pod#Encode_decode_xs_n-byte_heap-overflow_%28CVE-2011-2939%29
- MDVSA-2012:008 vendor-advisory
- RHSA-2011:1424 vendor-advisory
- [oss-security] 20110819 Re: CVE request: heap overflow in perl while decoding Unicode string mailing-list
- 51457 third-party-advisory