CVE-2018-20103: canonical ubuntu_linux Loop with Unreachable Exit Condition
Vulnerability summary
CVE-2018-20103 is a high (CVSS 7.5) Loop with Unreachable Exit Condition vulnerability in canonical ubuntu_linux. EPSS estimates a 6.59% chance of exploitation in the next 30 days, higher than 93.8% of scored vulnerabilities.
Severe, CVSS 7.5 (NVD); no exploitation reported by the 5 checked sources; EPSS 7% (FIRST, 03-11-2026)
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 6 · Related 3Timeline
- 12-12-2018PublishedVulnerability first disclosed.
- 05-08-2024Last modifiedVulnerability information updated.
Description
An issue was discovered in dns.c in HAProxy through 1.8.14. In the case of a compressed pointer, a crafted packet can trigger infinite recursion by making the pointer point to itself, or create a long chain of valid pointers resulting in stack exhaustion.
CVSS metrics
4 scores · 3 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
- OSV · DebianEcosystem advisory · calculated7.5HighCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS trend
Probability
6.59%
Chance of exploitation in the next 30 days
Percentile
94%
Versus all other CVEs
30-day change
No change 0.00 pp
From 6.59% 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.
Canonical1 product
- ubuntu_linuxEOL16.04 | 18.04 | 18.10
Debian1 product
- haproxy< 1.8.15-1
Haproxy1 product
- haproxy≤ 1.8.14
Redhat1 product
Ubuntu1 product
- haproxy< 1.8.8-1ubuntu0.3
5 vendors · 5 products
