CVE-2021-3909: cloudflare octorpki Uncontrolled Resource Consumption
Vulnerability summary
CVE-2021-3909 is a high (CVSS 7.5) Uncontrolled Resource Consumption vulnerability in cloudflare octorpki. EPSS estimates a 1.57% chance of exploitation in the next 30 days, higher than 75% of scored vulnerabilities.
Advisory lineage
Upstream 0 · Downstream 2Timeline
- 11-11-2021PublishedVulnerability first disclosed.
- 16-09-2024Last modifiedVulnerability information updated.
Description
OctoRPKI does not limit the length of a connection, allowing for a slowloris DOS attack to take place which makes OctoRPKI wait forever. Specifically, the repository that OctoRPKI sends HTTP requests to will keep the connection open for a day before a response is returned, but does keep drip feeding new bytes to keep the connection alive.
CVSS metrics
6 scores · 5 sources · 2 versions- CVE.orgCNA4.4MediumCVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:HDiffers
- OSV · UbuntuEcosystem advisory · calculated4.4MediumCVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:HDiffers
- OSV · DebianEcosystem advisory · calculated7.5HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- OSV · GoEcosystem advisory · calculated4.4MediumCVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:HDiffers
EPSS trend
Probability
1.57%
Chance of exploitation in the next 30 days
Percentile
75%
Versus all other CVEs
30-day change
+0.01 pp
From 1.56% on 19-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Debian4 products
- cfrpki< 1.4.0-1
- fort-validator< 1.5.3-1
- rpki-client< 7.5-1
- debian_linuxEOL11.0
Cloudflare1 product
- octorpki≥ unspecified, < 1.4.0 | < 1.3.0
Github.com/cloudflare1 product
- cfrpki< 1.4.0
Ubuntu1 product
- cfrpki< 1.4.2-1
4 vendors · 7 products
References
11 links- github.com/cloudflare/cfrpki/security/advisories/GHSA-8cvr-4rrf-f244X Refsource MISCREPORTWEBAdvisoryThird Party Advisory
- github.com/cloudflare/cfrpkiPACKAGE