CVE-2020-16154
Description
A flaw was found in the way the perl-App-cpanminus performed verification of package signatures stored in CHECKSUMS files. A malicious or compromised CPAN server used by a user, or a man-in-the-middle attacker, could use this flaw to bypass signature verification.
Mitigation
This issue can be mitigated by instructing perl-App-cpanminus to only use trusted CPAN mirrors (www.cpan.org or cpan.metacpan.org) and use HTTPS for communication with CPAN servers. The `cpanm` command can be configured to use the specific CPAN mirror using the --from command line option by running it as:
cpanm --from https://www.cpan.org ...
You can also set environment variable PERL_CPANM_OPT to include this command line option to avoid having to specify the URL for every cpanm invocation:
export PERL_CPANM_OPT="--from https://www.cpan.org"
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
The following CVSS metrics and score provided are preliminary and subject to review.
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 7.8 | 7.8 | N/A |
| Attack Vector | Local | Local | N/A |
| Attack Complexity | Low | Low | N/A |
| Privileges Required | None | None | N/A |
| User Interaction | Required | Required | N/A |
| Scope | Unchanged | Unchanged | N/A |
| Confidentiality | High | High | N/A |
| Integrity Impact | High | High | N/A |
| Availability Impact | High | High | N/A |
Vector
Red Hat: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
NVD: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Understanding the Weakness (CWE)
Access Control,Integrity,Confidentiality
Technical Impact: Gain Privileges or Assume Identity; Modify Application Data; Execute Unauthorized Code or Commands
An attacker could gain access to sensitive data and possibly execute unauthorized code.
Frequently Asked Questions
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