CVE-2021-36770
Published: August 31, 2023Last modified: August 31, 2023
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.
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score | 7.8 |
| Attack Vector | LOCAL |
| Attack complexity | LOW |
| Privileges required | NONE |
| User interaction | REQUIRED |
| Scope | UNCHANGED |
| Confidentiality | HIGH |
| Integrity impact | HIGH |
| Availability impact | HIGH |
| Vector | CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H |
Status
| Product | Release | Package | Status |
|---|---|---|---|
| Alpaquita Linux | 23 LTS | perl | Not affected (5.36.0-r2) |
| Stream | perl | Not affected (5.38.0-r0) |
References
- https://github.com/Perl/perl5/commit/c1a937fef07c061600a0078f4cb53fe9c2136bb9
- https://github.com/dankogai/p5-encode/commit/527e482dc70b035d0df4f8c77a00d81f8d775c74
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5NDGQSGMEZ75FJGBKNYC75OTO7TF7XHB/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/6KOZYD7BH2DNIAEZ2ZL4PJ4QUVQI6Y33/
- https://lists.fedoraproject.org/archives/list/[email protected]/message/5NDGQSGMEZ75FJGBKNYC75OTO7TF7XHB/
- https://lists.fedoraproject.org/archives/list/[email protected]/message/6KOZYD7BH2DNIAEZ2ZL4PJ4QUVQI6Y33/
- https://metacpan.org/dist/Encode/changes
- https://news.cpanel.com/unscheduled-tsr-10-august-2021/
- https://security-tracker.debian.org/tracker/CVE-2021-36770
- https://security.netapp.com/advisory/ntap-20210909-0003/