CVE-2019-16201: debian debian_linux Improper Authentication
Vulnerability summary
CVE-2019-16201 is a high (CVSS 7.8) Improper Authentication vulnerability in debian debian_linux. EPSS estimates a 5.09% chance of exploitation in the next 30 days, higher than 92.3% of scored vulnerabilities.
Severe, CVSS 7.5 (NVD); no exploitation reported by the 5 checked sources; EPSS 5% (FIRST, 03-11-2026)
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 18 · Related 4Timeline
- 26-11-2019PublishedVulnerability first disclosed.
- 05-08-2024Last modifiedVulnerability information updated.
Description
WEBrick::HTTPAuth::DigestAuth in Ruby through 2.4.7, 2.5.x through 2.5.6, and 2.6.x through 2.6.4 has a regular expression Denial of Service cause by looping/backtracking. A victim must expose a WEBrick server that uses DigestAuth to the Internet or a untrusted network.
CVSS metrics
5 scores · 4 sources · 2 versions- OSV · AlpineEcosystem advisory · calculated7.5HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- OSV · UbuntuEcosystem advisory · calculated7.5HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- OSV · DebianEcosystem advisory · calculated7.5HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS trend
Probability
5.09%
Chance of exploitation in the next 30 days
Percentile
92%
Versus all other CVEs
30-day change
Decrease -0.04 pp
From 5.13% on 04-10-2026
Known exploited
Compare KEV catalogs
CISA KEVNot in the CISA KEV catalog.
ENISA CNWNot in the ENISA CNW catalog.
CIRCLNot in the CIRCL catalog.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Known conditions: network-reachable, no authentication, no user interaction (CVSS vector). Other conditions: not stated in public data.
Ubuntu3 products
- jruby< 1.5.6-9+deb8u2build0.14.04.1~esm2 | All versions (No fix recorded)
- ruby2.3< 2.3.1-2~ubuntu16.04.14
- ruby2.5< 2.5.1-1ubuntu1.6
Debian2 products
- jruby< 9.3.9.0+ds-1
- debian_linuxEOL8.0
Alpine1 product
- ruby≥ 2.4.0, < 2.5.7-r0 | ≥ 2.4.0, < 2.6.5-r0 | ≥ 2.4.0, < 2.4.10-r0
Ruby-lang1 product
- ruby≥ 2.4.0, ≤ 2.4.7 | ≥ 2.5.0, ≤ 2.5.6 | ≥ 2.6.0, ≤ 2.6.4
4 vendors · 7 products
References
18 links- hackerone.com/reports/661722Third Party Advisory
- seclists.org/bugtraq/2019/Dec/31Mailing List
- seclists.org/bugtraq/2019/Dec/32Mailing List
- www.debian.org/security/2019/dsa-4587Vendor Advisory
- security.gentoo.org/glsa/202003-06Vendor Advisory
