CVE-2017-6056: canonical ubuntu_linux Loop with Unreachable Exit Condition
Vulnerability summary
CVE-2017-6056 is a high (CVSS 7.5) Loop with Unreachable Exit Condition vulnerability in canonical ubuntu_linux. EPSS estimates a 7.58% chance of exploitation in the next 30 days, higher than 94.5% of scored vulnerabilities.
Severe, CVSS 7.5 (NVD); no exploitation reported by the 5 checked sources; EPSS 8% (FIRST, 03-11-2026)
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 4Timeline
- 17-02-2017PublishedVulnerability first disclosed.
- 05-08-2024Last modifiedVulnerability information updated.
Description
It was discovered that a programming error in the processing of HTTPS requests in the Apache Tomcat servlet and JSP engine may result in denial of service via an infinite loop. The denial of service is easily achievable as a consequence of backporting a CVE-2016-6816 fix but not backporting the fix for Tomcat bug 57544. Distributions affected by this backporting issue include Debian (before 7.0.56-3+deb8u8 and 8.0.14-1+deb8u7 in jessie) and Ubuntu.
CVSS metrics
3 scores · 2 sources · 2 versions- 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
7.58%
Chance of exploitation in the next 30 days
Percentile
95%
Versus all other CVEs
30-day change
Increase +0.09 pp
From 7.49% 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.
Debian3 products
- tomcat7< 7.0.56-3+deb8u8 | < 7.0.28-4+deb7u10
- tomcat8< 8.0.14-1+deb8u7
- debian_linuxEOL8.0
Ubuntu2 products
- tomcat6< 6.0.39-1ubuntu0.1+esm1
- tomcat7< 7.0.52-1ubuntu0.10
Canonical1 product
- ubuntu_linuxEOL12.04 | 14.04
3 vendors · 6 products
