CVE-2020-27637: The R programming language’s default package manager CRAN is affected by a path traversal vulnerability that c

Q: How do I fix CVE-2020-27637?

cran: upgrade to 4.0.3. Exact commands for each OS are on this page.

Q: Is CVE-2020-27637 being exploited?

CVE-2020-27637 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

Q: What does CVE-2020-27637 affect?

CVE-2020-27637 affects cran. Severity is critical (CVSS 9.8). The R programming language’s default package manager CRAN is affected by a path traversal vulnerability that can lead to server compromise. This vulnerability affects packages installed via the R CMD install cli command or the install.packa

Q: How urgent is CVE-2020-27637?

Priority 65/100. Critical severity; Public exploit reference; Remotely exploitable, no login, no user action

This week

CRITICAL 9.8REMOTEUPGRADE

CVE-2020-27637 is a critical-severity flaw (CVSS 9.8) affecting cran. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

The R programming language’s default package manager CRAN is affected by a path traversal vulnerability that can lead to server compromise. This vulnerability affects packages installed via the R CMD install cli command or the install.packages() function from the interpreter. Update to version 4.0.3

Why this priority

Critical severity
Public exploit reference
Remotely exploitable, no login, no user action

A fixed release or distro patch exists.

Risk facts

CVSS score	9.8 (Critical)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	2.3% (top 17%)
CISA exploited list	No
Weakness	CWE-22
Published	2021-01-12
Last modified	2026-06-17

Publisher (CNA): MITRE · Vendor: r-project

Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2021-01-12 04:15 UTCPublished CVE record published
2026-06-17 03:09 UTCUpdated Record last modified

r-project cran UPGRADE

Affected: < 4.0.3

Fixed in: 4.0.3

Safe to downgrade to: no unaffected older release

1. Check installed version

apt-cache policy cran || rpm -q cran || cran --version

2. UPGRADE to 4.0.3 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade cran

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade cran

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2020-27637?

cran: upgrade to 4.0.3. Exact commands for each OS are on this page.

Is CVE-2020-27637 being exploited?

CVE-2020-27637 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2020-27637 affect?

CVE-2020-27637 affects cran. Severity is critical (CVSS 9.8). The R programming language’s default package manager CRAN is affected by a path traversal vulnerability that can lead to server compromise. This vulnerability affects packages installed via the R CMD install cli command or the install.packa

How urgent is CVE-2020-27637?

Priority 65/100. Critical severity; Public exploit reference; Remotely exploitable, no login, no user action

References

← Back to latest CVEs