Vulnerability · Published Aug 11, 2021 · Assigned by mitre
CVE-2021-36770
High 7.8
In plain English
A high-severity security flaw in the perl package (Alpine). There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 1.4% (higher than 72% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
Encode.pm, as distributed in Perl through 5.34.0, allows local users to gain privileges via a Trojan horse Encode::ConfigLocal library (in the current working directory) that preempts dynamic module loading. Exploitation requires an unusual configuration, and certain 2021 versions of Encode.pm (3.05 through 3.11). This issue occurs because the || operator evaluates @INC in a scalar context, and thus @INC has only an integer value.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine:v3.20 | perl | 5.34.0-r1 | ALPINE-CVE-2021-36770 |
| Alpine:v3.21 | perl | 5.34.0-r1 | ALPINE-CVE-2021-36770 |
| Alpine:v3.22 | perl | 5.34.0-r1 | ALPINE-CVE-2021-36770 |
| Alpine:v3.23 | perl | 5.34.0-r1 | ALPINE-CVE-2021-36770 |
| Alpine:v3.24 | perl | 5.34.0-r1 | ALPINE-CVE-2021-36770 |
| Alpine:v3.20 | perl-encode | 3.12-r0 | ALPINE-CVE-2021-36770 |
| Alpine:v3.21 | perl-encode | 3.12-r0 | ALPINE-CVE-2021-36770 |
| Alpine:v3.22 | perl-encode | 3.12-r0 | ALPINE-CVE-2021-36770 |
| Alpine:v3.23 | perl-encode | 3.12-r0 | ALPINE-CVE-2021-36770 |
| Alpine:v3.24 | perl-encode | 3.12-r0 | ALPINE-CVE-2021-36770 |
| Debian:12 | libencode-perl | 3.08-2 | DEBIAN-CVE-2021-36770 |
| Debian:13 | libencode-perl | 3.08-2 | DEBIAN-CVE-2021-36770 |
| Debian:14 | libencode-perl | 3.08-2 | DEBIAN-CVE-2021-36770 |
| Debian:12 | perl | 5.32.1-5 | DEBIAN-CVE-2021-36770 |
| Debian:13 | perl | 5.32.1-5 | DEBIAN-CVE-2021-36770 |
| Debian:14 | perl | 5.32.1-5 | DEBIAN-CVE-2021-36770 |
| Ubuntu:22.04:LTS | libencode-perl | no fix listed | UBUNTU-CVE-2021-36770 |
| Ubuntu:24.04:LTS | libencode-perl | no fix listed | UBUNTU-CVE-2021-36770 |
| Ubuntu:25.10 | libencode-perl | no fix listed | UBUNTU-CVE-2021-36770 |
| Ubuntu:26.04:LTS | libencode-perl | no fix listed | UBUNTU-CVE-2021-36770 |
| Ubuntu:26.10 | libencode-perl | no fix listed | UBUNTU-CVE-2021-36770 |
| Ubuntu:22.04:LTS | perl | 5.32.1-3ubuntu3 | UBUNTU-CVE-2021-36770 |
Affected products (as reported)
References
- https://metacpan.org/dist/Encode/changes x_refsource_CONFIRM
- https://security-tracker.debian.org/tracker/CVE-2021-36770 x_refsource_MISC
- https://github.com/dankogai/p5-encode/commit/527e482dc70b035d0df4f8c77a00d81f8d775c74 x_refsource_CONFIRM
- https://github.com/Perl/perl5/commit/c1a937fef07c061600a0078f4cb53fe9c2136bb9 x_refsource_CONFIRM
- https://news.cpanel.com/unscheduled-tsr-10-august-2021/ x_refsource_CONFIRM
- FEDORA-2021-92e07de1dd vendor-advisory, x_refsource_FEDORA
- FEDORA-2021-44c65203cc vendor-advisory, x_refsource_FEDORA
- https://security.netapp.com/advisory/ntap-20210909-0003/ x_refsource_CONFIRM
- https://security.netapp.com/advisory/ntap-20241108-0002/