CVE-2018-8777: canonical ubuntu_linux Uncontrolled Resource Consumption
Vulnerability summary
CVE-2018-8777 is a high (CVSS 7.5) Uncontrolled Resource Consumption vulnerability in canonical ubuntu_linux. EPSS estimates a 4.46% chance of exploitation in the next 30 days, higher than 91.4% of scored vulnerabilities.
Severe, CVSS 7.5 (NVD); no exploitation reported by the 5 checked sources; EPSS 4% (FIRST, 04-11-2026)
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 16 · Related 4Timeline
- 03-04-2018PublishedVulnerability first disclosed.
- 05-08-2024Last modifiedVulnerability information updated.
Description
In Ruby before 2.2.10, 2.3.x before 2.3.7, 2.4.x before 2.4.4, 2.5.x before 2.5.1, and 2.6.0-preview1, an attacker can pass a large HTTP request with a crafted header to WEBrick server or a crafted body to WEBrick server/handler and cause a denial of service (memory consumption).
CVSS metrics
4 scores · 3 sources · 2 versions- OSV · AlpineEcosystem advisory · calculated7.5HighCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- OSV · UbuntuEcosystem advisory · calculated7.5HighCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS trend
Probability
4.46%
Chance of exploitation in the next 30 days
Percentile
91%
Versus all other CVEs
30-day change
No change 0.00 pp
From 4.46% on 05-10-2026
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
- ruby1.9.1< 1.9.3.484-2ubuntu1.12
- ruby2.0< 2.0.0.484-1ubuntu2.10
- ruby2.3< 2.3.1-2~16.04.10
Alpine1 product
- ruby≥ 2.2.0, < 2.5.1-r0 | ≥ 2.2.0, < 2.3.7-r0 | ≥ 2.2.0, < 2.4.4-r0
Canonical1 product
- ubuntu_linuxEOL14.04 | 16.04 | 17.10
Debian1 product
- debian_linuxEOL7.0 | 8.0 | 9.0
Redhat1 product
- enterprise_linuxEOL6.0 | 7.0 | 7.4 | 7.5 | 7.6
Ruby-lang1 product
- rubyEOL≥ 2.2.0, < 2.2.10 | ≥ 2.3.0, < 2.3.7 | ≥ 2.4.0, < 2.4.4 | ≥ 2.5.0, < 2.5.1 | 2.6.0:preview1
6 vendors · 8 products
References
24 links- www.ruby-lang.org/en/news/2018/03/28/large-request-dos-in-webrick-cve-2018-8777/X Refsource CONFIRMVendor AdvisoryREPORT
lists.debian.org/debian-lts-announce/2018/04/msg00023.htmlMailing ListX Refsource MLISTThird Party Advisory
Show all 24 references
- lists.debian.org/debian-lts-announce/2018/07/msg00012.htmlMailing ListX Refsource MLISTThird Party Advisory
- lists.debian.org/debian-lts-announce/2018/04/msg00024.htmlMailing ListX Refsource MLISTThird Party Advisory