CVE-2018-20102: canonical ubuntu_linux Out-of-bounds Read
Vulnerability summary
CVE-2018-20102 is a high (CVSS 7.5) Out-of-bounds Read vulnerability in canonical ubuntu_linux. EPSS estimates a 4.15% chance of exploitation in the next 30 days, higher than 90.8% of scored vulnerabilities.
Severe, CVSS 7.5 (NVD); no exploitation reported by the 5 checked sources; EPSS 4% (FIRST, 03-11-2026)
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 6 · Related 2Timeline
- 12-12-2018PublishedVulnerability first disclosed.
- 05-08-2024Last modifiedVulnerability information updated.
Description
An out-of-bounds read in dns_validate_dns_response in dns.c was discovered in HAProxy through 1.8.14. Due to a missing check when validating DNS responses, remote attackers might be able read the 16 bytes corresponding to an AAAA record from the non-initialized part of the buffer, possibly accessing anything that was left on the stack, or even past the end of the 8193-byte buffer, depending on the value of accepted_payload_size.
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:H/I:N/A:N
- OSV · DebianEcosystem advisory · calculated7.5HighCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
EPSS trend
Probability
4.15%
Chance of exploitation in the next 30 days
Percentile
91%
Versus all other CVEs
30-day change
No change 0.00 pp
From 4.15% 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< 1.6.3-1ubuntu0.2 | < 1.8.8-1ubuntu0.3
5 vendors · 5 products
