CVE-2021-3978 | Improper Preservation of Permissions in github.com/cloudflare/cfrpki/cmd/octorpki

When copying files with rsync, octorpki uses the "-a" flag 0, which forces rsync to copy binaries with the suid bit set as root. Since the provided service definition defaults to root ( https://github.com/cloudflare/cfrpki/blob/master/package/octorpki.service ) this could allow for a vector, when combined with another vulnerability that causes octorpki to process a malicious TAL file, for a local privilege escalation.

Published: 2025-01-29 Last update: 2025-07-29 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2021-3978 is rated Low Risk (38.5/100): CVSS High severity, with low exploitation likelihood (EPSS 0.08%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2021-3978

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-03-09 0.04% 0.08% +0.04%
2 2025-01-30 0.04%

Full EPSS history (2 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-3978

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:C/C:H/I:H/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
0.8 6.0 [email protected]
5.5 3.1 MEDIUM
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N)
Service keeps running; no real outage angle.
1.8 3.6 [email protected]

Weakness enumeration for CVE-2021-3978

GitHub Security Advisory for CVE-2021-3978

GHSA-3pqh-p72c-fj85 · Severity: high · Ecosystem: go — Improper Preservation of Permissions in github.com/cloudflare/cfrpki/cmd/octorpki

OS Trackers for CVE-2021-3978

vendor priority summary link
debian not yet assigned CVE-2021-3978 not yet assigned priority: Debian including 1 source packages (cfrpki), 2 status rows across 2 suites (bookworm, bullseye): resolved 2. https://security-tracker.debian.org/tracker/CVE-2021-3978
ubuntu medium CVE-2021-3978 medium priority: Ubuntu including 1 source packages (cfrpki), 5 status rows across 5 suites (focal, jammy, noble, oracular, upstream): DNE 3, not-affected 1, released 1. https://ubuntu.com/security/CVE-2021-3978

Affected software / configurations for CVE-2021-3978

Vendor Product Version Raw CPE
cloudflare octorpki < 1.4.2 cpe:2.3:a:cloudflare:octorpki:*:*:*:*:*:*:*:*

References for CVE-2021-3978

cvelogic Threat Intelligence