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CVE-2019-16201· NVD / CVE Program· CNA mitre

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

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.

HighCVSS 7.5 · v3.1—No exploit Fix available
Published
Nov 26, 2019
Updated
Jun 16, 2026
EPSS
5.1% · 92th percentile
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Report tools

JSON

Action score

32

Monitor

Low priority for now.

CVSS
30 / 40 · 7.5 / 10
CISA KEV
0 / 30 · Not listed
EPSS
2 / 30 · 5.1%

Affected systems

VendorProduct
ruby-langruby
debiandebian linux

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • debian debian linux8.0
  • ruby-lang ruby2.4.0 and later · up to 2.4.7 inclusive
  • ruby-lang ruby2.5.0 and later · up to 2.5.6 inclusive
  • ruby-lang ruby2.6.0 and later · up to 2.6.4 inclusive

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
AlmaLinux:8rubygem-abrtbefore 0.3.0-4.module_el8.5.0+2625+ec4185530.3.0-4.module_el8.5.0+2625+ec418553
AlmaLinux:8rubygem-abrtbefore 0.3.0-4.module_el8.5.0+2623+08a8ba320.3.0-4.module_el8.5.0+2623+08a8ba32
AlmaLinux:8rubygem-abrtbefore 0.3.0-4.module_el8.5.0+259+8cec69170.3.0-4.module_el8.5.0+259+8cec6917
AlmaLinux:8rubygem-abrt-docbefore 0.3.0-4.module_el8.5.0+2623+08a8ba320.3.0-4.module_el8.5.0+2623+08a8ba32
AlmaLinux:8rubygem-abrt-docbefore 0.3.0-4.module_el8.5.0+2625+ec4185530.3.0-4.module_el8.5.0+2625+ec418553
AlmaLinux:8rubygem-abrt-docbefore 0.3.0-4.module_el8.5.0+259+8cec69170.3.0-4.module_el8.5.0+259+8cec6917
AlmaLinux:8rubygem-bsonbefore 4.3.0-2.module_el8.5.0+2625+ec4185534.3.0-2.module_el8.5.0+2625+ec418553
AlmaLinux:8rubygem-bsonbefore 4.3.0-2.module_el8.5.0+259+8cec69174.3.0-2.module_el8.5.0+259+8cec6917
AlmaLinux:8rubygem-bsonbefore 4.5.0-1.module_el8.5.0+250+ba22dbf74.5.0-1.module_el8.5.0+250+ba22dbf7
AlmaLinux:8rubygem-bsonbefore 4.5.0-1.module_el8.5.0+2623+08a8ba324.5.0-1.module_el8.5.0+2623+08a8ba32
AlmaLinux:8rubygem-bson-docbefore 4.3.0-2.module_el8.5.0+2625+ec4185534.3.0-2.module_el8.5.0+2625+ec418553
AlmaLinux:8rubygem-bson-docbefore 4.5.0-1.module_el8.5.0+250+ba22dbf74.5.0-1.module_el8.5.0+250+ba22dbf7
AlmaLinux:8rubygem-bson-docbefore 4.5.0-1.module_el8.5.0+2623+08a8ba324.5.0-1.module_el8.5.0+2623+08a8ba32
AlmaLinux:8rubygem-bson-docbefore 4.3.0-2.module_el8.5.0+259+8cec69174.3.0-2.module_el8.5.0+259+8cec6917
AlmaLinux:8rubygem-mongobefore 2.8.0-1.module_el8.5.0+2623+08a8ba322.8.0-1.module_el8.5.0+2623+08a8ba32
AlmaLinux:8rubygem-mongobefore 2.8.0-1.module_el8.5.0+250+ba22dbf72.8.0-1.module_el8.5.0+250+ba22dbf7
AlmaLinux:8rubygem-mongobefore 2.5.1-2.module_el8.5.0+259+8cec69172.5.1-2.module_el8.5.0+259+8cec6917
AlmaLinux:8rubygem-mongobefore 2.5.1-2.module_el8.5.0+2625+ec4185532.5.1-2.module_el8.5.0+2625+ec418553
AlmaLinux:8rubygem-mongo-docbefore 2.5.1-2.module_el8.5.0+259+8cec69172.5.1-2.module_el8.5.0+259+8cec6917
AlmaLinux:8rubygem-mongo-docbefore 2.8.0-1.module_el8.5.0+250+ba22dbf72.8.0-1.module_el8.5.0+250+ba22dbf7
AlmaLinux:8rubygem-mongo-docbefore 2.8.0-1.module_el8.5.0+2623+08a8ba322.8.0-1.module_el8.5.0+2623+08a8ba32
AlmaLinux:8rubygem-mongo-docbefore 2.5.1-2.module_el8.5.0+2625+ec4185532.5.1-2.module_el8.5.0+2625+ec418553
AlmaLinux:8rubygem-mysql2before 0.4.10-4.module_el8.5.0+2625+ec4185530.4.10-4.module_el8.5.0+2625+ec418553
AlmaLinux:8rubygem-mysql2before 0.4.10-4.module_el8.5.0+259+8cec69170.4.10-4.module_el8.5.0+259+8cec6917

+96

Same product

ruby-lang: all records

Other highest-scoring records for the same primary product.

  • CVE-2017-17405Ruby before 2.4.3 allows Net::FTP command injection.
    57Plan
  • CVE-2008-3656Algorithmic complexity vulnerability in the WEBrick::HTTPUtils.split_header_value function in WEBrick::HTTP::DefaultFileHandler in WEBrick i
    52Plan
  • CVE-2021-28966In Ruby through 3.0 on Windows, a remote attacker can submit a crafted path when a Web application handles a parameter with TmpDir.
    47Plan
  • CVE-2017-14064Ruby through 2.2.7, 2.3.x through 2.3.4, and 2.4.x through 2.4.1 can expose arbitrary memory during a JSON.generate call.
    42Plan
  • CVE-2017-17790The lazy_initialize function in lib/resolv.rb in Ruby through 2.4.3 uses Kernel#open, which might allow Command Injection attacks, as demons
    41Plan
  • CVE-2016-2339An exploitable heap overflow vulnerability exists in the Fiddle::Function.new "initialize" function functionality of Ruby.
    41Plan

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
almalinux:rubygem-abrt0.3.0-4.module_el8.5.0+2625+ec418553 · AlmaLinux:8Package registry (OSV)
almalinux:rubygem-abrt-doc0.3.0-4.module_el8.5.0+259+8cec6917 · AlmaLinux:8Package registry (OSV)
almalinux:rubygem-bson4.3.0-2.module_el8.5.0+2625+ec418553 · AlmaLinux:8Package registry (OSV)
almalinux:rubygem-bson-doc4.3.0-2.module_el8.5.0+2625+ec418553 · AlmaLinux:8Package registry (OSV)
almalinux:rubygem-mongo2.5.1-2.module_el8.5.0+259+8cec6917 · AlmaLinux:8Package registry (OSV)
almalinux:rubygem-mongo-doc2.5.1-2.module_el8.5.0+2625+ec418553 · AlmaLinux:8Package registry (OSV)
almalinux:rubygem-mysql20.4.10-4.module_el8.5.0+259+8cec6917 · AlmaLinux:8Package registry (OSV)
almalinux:rubygem-mysql2-doc0.4.10-4.module_el8.5.0+2625+ec418553 · AlmaLinux:8Package registry (OSV)
almalinux:rubygem-pg1.0.0-2.module_el8.5.0+2625+ec418553 · AlmaLinux:8Package registry (OSV)
almalinux:rubygem-pg-doc1.0.0-2.module_el8.5.0+2625+ec418553 · AlmaLinux:8Package registry (OSV)
alpine:ruby2.5.7-r0 · Alpine:v3.10Package registry (OSV)
debian:jruby9.3.9.0+ds-1 · Debian:12Package registry (OSV)
debian:ruby2.12.1.5-2+deb8u8 · Debian:8Package registry (OSV)
debian:ruby2.32.3.3-1+deb9u7 · Debian:9Package registry (OSV)
debian:ruby2.52.5.5-3+deb10u1 · Debian:10Package registry (OSV)
opensuse:ruby2.52.5.7-lp151.4.6.1 · openSUSE:Leap 15.1Package registry (OSV)
red hat:rh-ruby25-ruby0:2.5.9-9.el7 · Red Hat:rhel_software_collections:3::el7Package registry (OSV)
red hat:rh-ruby25-ruby-debuginfo0:2.5.9-9.el7 · Red Hat:rhel_software_collections:3::el7Package registry (OSV)
red hat:rh-ruby25-ruby-devel0:2.5.9-9.el7 · Red Hat:rhel_software_collections:3::el7Package registry (OSV)
red hat:rh-ruby25-ruby-doc0:2.5.9-9.el7 · Red Hat:rhel_software_collections:3::el7Package registry (OSV)
red hat:rh-ruby25-ruby-irb0:2.5.9-9.el7 · Red Hat:rhel_software_collections:3::el7Package registry (OSV)
red hat:rh-ruby25-ruby-libs0:2.5.9-9.el7 · Red Hat:rhel_software_collections:3::el7Package registry (OSV)
red hat:rh-ruby25-rubygem-bigdecimal0:1.3.4-9.el7 · Red Hat:rhel_software_collections:3::el7Package registry (OSV)
red hat:rh-ruby25-rubygem-did_you_mean0:1.2.0-9.el7 · Red Hat:rhel_software_collections:3::el7Package registry (OSV)
red hat:rh-ruby25-rubygem-io-console0:0.4.6-9.el7 · Red Hat:rhel_software_collections:3::el7Package registry (OSV)
red hat:rh-ruby25-rubygem-json0:2.1.0-9.el7 · Red Hat:rhel_software_collections:3::el7Package registry (OSV)
red hat:rh-ruby25-rubygem-minitest0:5.10.3-9.el7 · Red Hat:rhel_software_collections:3::el7Package registry (OSV)
red hat:rh-ruby25-rubygem-net-telnet0:0.1.1-9.el7 · Red Hat:rhel_software_collections:3::el7Package registry (OSV)
rocky linux:ruby0:2.5.9-107.module+el8.4.0+592+03ff458a · Rocky Linux:8Package registry (OSV)
rocky linux:rubygem-abrt0:0.3.0-4.module+el8.5.0+738+032c9c02 · Rocky Linux:8Package registry (OSV)

+6

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

No nightly-computed relations.

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

The product’s vendor appears in a public program. Matched by name; verify the scope text in the program.

Technical details

Attack conditions

  • Anyone who can reach it over the internet can trigger it.
  • No account or password is required.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
none
Integrity
none
Availability
high · the service can be disrupted
Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality impact
None
Integrity impact
None
Availability impact
High

Weakness class (CWE)

CWE-287 · Improper Authentication

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

nvd-primary

Root cause

Authentication is added route by route instead of being enforced in one place. When a route added later bypasses the shared middleware, the session check never runs for it.

The bug in code

The whole CWE-287 class

A representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.

Vulnerable

ts
app.use("/admin", requireSession, adminRouter);
// Route added later skips the middlewareapp.post("/admin-api/config", updateConfig);

Fixed

ts
const admin = express.Router();admin.use(requireSession, requireRole("admin"));
admin.post("/config", updateConfig);app.use("/admin", admin);

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

Noroxi analysis

No Noroxi analysis for this record yet

We don't hand-write analysis for all 385,000+ vulnerabilities; that wouldn't be honest. For notable, high-impact vulnerabilities our team writes the mechanism, detection and remediation steps.

We use this product, ask for help

Change log

  1. Fix✗ → ✓

For records you follow, these changes also arrive as notifications. →

References

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records