CVE-2015-3281

The buffer_slow_realign function in HAProxy 1.5.x before 1.5.14 and 1.6-dev does not properly realign a buffer that is used for pending outgoing data, which allows remote attackers to obtain sensitive information (uninitialized memory contents of previous requests) via a crafted request.

Published: 2015-07-06 Last update: 2026-05-06 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2015-3281 is rated Moderate Risk (55.5/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 4.24%). EPSS rose +4.14% over the last day, indicating growing attacker interest. Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2015-3281

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.09% 4.24% +4.14%
2 2025-03-30 0.22% 0.09% -0.13%
3 2025-03-29 — 0.22% —

Full EPSS history (8 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2015-3281

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.0 2.0 MEDIUM
AV:N/AC:L/Au:N/C:P/I:N/A:N Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:N)
No integrity impact.
Availability impact (A:N)
No availability impact.
 10.0 2.9 [email protected]

Weakness enumeration for CVE-2015-3281

OS Trackers for CVE-2015-3281

vendor priority summary link
debian not yet assigned CVE-2015-3281 not yet assigned priority: Debian including 1 source packages (haproxy), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2015-3281
redhat high — https://access.redhat.com/security/cve/CVE-2015-3281
ubuntu medium CVE-2015-3281 medium priority: Ubuntu including 1 source packages (haproxy), 5 status rows across 5 suites (precise, trusty, upstream, utopic, vivid): released 3, DNE 1, not-affected 1. https://ubuntu.com/security/CVE-2015-3281

Affected software / configurations for CVE-2015-3281

Vendor Product Version Raw CPE
debian debian_linux 8.0 cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*
haproxy haproxy 1.5 cpe:2.3:a:haproxy:haproxy:1.5:dev:*:*:*:*:*:*
haproxy haproxy 1.5 cpe:2.3:a:haproxy:haproxy:1.5:dev0:*:*:*:*:*:*
haproxy haproxy 1.5 cpe:2.3:a:haproxy:haproxy:1.5:dev1:*:*:*:*:*:*
haproxy haproxy 1.5 cpe:2.3:a:haproxy:haproxy:1.5:dev10:*:*:*:*:*:*
haproxy haproxy 1.5 cpe:2.3:a:haproxy:haproxy:1.5:dev11:*:*:*:*:*:*
haproxy haproxy 1.5 cpe:2.3:a:haproxy:haproxy:1.5:dev12:*:*:*:*:*:*
haproxy haproxy 1.5 cpe:2.3:a:haproxy:haproxy:1.5:dev13:*:*:*:*:*:*
haproxy haproxy 1.5 cpe:2.3:a:haproxy:haproxy:1.5:dev14:*:*:*:*:*:*
haproxy haproxy 1.5 cpe:2.3:a:haproxy:haproxy:1.5:dev15:*:*:*:*:*:*
haproxy haproxy 1.5 cpe:2.3:a:haproxy:haproxy:1.5:dev16:*:*:*:*:*:*
haproxy haproxy 1.5 cpe:2.3:a:haproxy:haproxy:1.5:dev17:*:*:*:*:*:*
haproxy haproxy 1.5 cpe:2.3:a:haproxy:haproxy:1.5:dev18:*:*:*:*:*:*
haproxy haproxy 1.5 cpe:2.3:a:haproxy:haproxy:1.5:dev19:*:*:*:*:*:*
haproxy haproxy 1.5 cpe:2.3:a:haproxy:haproxy:1.5:dev2:*:*:*:*:*:*
haproxy haproxy 1.5 cpe:2.3:a:haproxy:haproxy:1.5:dev3:*:*:*:*:*:*
haproxy haproxy 1.5 cpe:2.3:a:haproxy:haproxy:1.5:dev4:*:*:*:*:*:*
haproxy haproxy 1.5 cpe:2.3:a:haproxy:haproxy:1.5:dev5:*:*:*:*:*:*
haproxy haproxy 1.5 cpe:2.3:a:haproxy:haproxy:1.5:dev6:*:*:*:*:*:*
haproxy haproxy 1.5 cpe:2.3:a:haproxy:haproxy:1.5:dev7:*:*:*:*:*:*
haproxy haproxy 1.5 cpe:2.3:a:haproxy:haproxy:1.5:dev8:*:*:*:*:*:*
haproxy haproxy 1.5 cpe:2.3:a:haproxy:haproxy:1.5:dev9:*:*:*:*:*:*
haproxy haproxy 1.5.0 cpe:2.3:a:haproxy:haproxy:1.5.0:*:*:*:*:*:*:*
haproxy haproxy 1.5.1 cpe:2.3:a:haproxy:haproxy:1.5.1:*:*:*:*:*:*:*
haproxy haproxy 1.5.2 cpe:2.3:a:haproxy:haproxy:1.5.2:*:*:*:*:*:*:*
haproxy haproxy 1.5.3 cpe:2.3:a:haproxy:haproxy:1.5.3:*:*:*:*:*:*:*
haproxy haproxy 1.5.4 cpe:2.3:a:haproxy:haproxy:1.5.4:*:*:*:*:*:*:*
haproxy haproxy 1.5.5 cpe:2.3:a:haproxy:haproxy:1.5.5:*:*:*:*:*:*:*
haproxy haproxy 1.5.6 cpe:2.3:a:haproxy:haproxy:1.5.6:*:*:*:*:*:*:*
haproxy haproxy 1.5.7 cpe:2.3:a:haproxy:haproxy:1.5.7:*:*:*:*:*:*:*
haproxy haproxy 1.5.8 cpe:2.3:a:haproxy:haproxy:1.5.8:*:*:*:*:*:*:*
haproxy haproxy 1.5.9 cpe:2.3:a:haproxy:haproxy:1.5.9:*:*:*:*:*:*:*
haproxy haproxy 1.5.10 cpe:2.3:a:haproxy:haproxy:1.5.10:*:*:*:*:*:*:*
haproxy haproxy 1.5.11 cpe:2.3:a:haproxy:haproxy:1.5.11:*:*:*:*:*:*:*
haproxy haproxy 1.5.12 cpe:2.3:a:haproxy:haproxy:1.5.12:*:*:*:*:*:*:*
haproxy haproxy 1.5.13 cpe:2.3:a:haproxy:haproxy:1.5.13:*:*:*:*:*:*:*
haproxy haproxy 1.6 cpe:2.3:a:haproxy:haproxy:1.6:dev0:*:*:*:*:*:*
canonical ubuntu_linux 14.10 cpe:2.3:o:canonical:ubuntu_linux:14.10:*:*:*:*:*:*:*
canonical ubuntu_linux 15.04 cpe:2.3:o:canonical:ubuntu_linux:15.04:*:*:*:*:*:*:*
opensuse openstack_cloud 5 cpe:2.3:o:opensuse:openstack_cloud:5:*:*:*:*:*:*:*
opensuse opensuse 13.2 cpe:2.3:o:opensuse:opensuse:13.2:*:*:*:*:*:*:*
suse linux_enterprise_high_availability_extension 12 cpe:2.3:o:suse:linux_enterprise_high_availability_extension:12:*:*:*:*:*:*:*
redhat enterprise_linux_desktop 7.0 cpe:2.3:o:redhat:enterprise_linux_desktop:7.0:*:*:*:*:*:*:*
redhat enterprise_linux_server 7.0 cpe:2.3:o:redhat:enterprise_linux_server:7.0:*:*:*:*:*:*:*
redhat enterprise_linux_server_aus 7.3 cpe:2.3:o:redhat:enterprise_linux_server_aus:7.3:*:*:*:*:*:*:*
redhat enterprise_linux_server_aus 7.4 cpe:2.3:o:redhat:enterprise_linux_server_aus:7.4:*:*:*:*:*:*:*
redhat enterprise_linux_server_aus 7.6 cpe:2.3:o:redhat:enterprise_linux_server_aus:7.6:*:*:*:*:*:*:*
redhat enterprise_linux_server_eus 7.1 cpe:2.3:o:redhat:enterprise_linux_server_eus:7.1:*:*:*:*:*:*:*
redhat enterprise_linux_server_eus 7.2 cpe:2.3:o:redhat:enterprise_linux_server_eus:7.2:*:*:*:*:*:*:*
redhat enterprise_linux_server_eus 7.3 cpe:2.3:o:redhat:enterprise_linux_server_eus:7.3:*:*:*:*:*:*:*
redhat enterprise_linux_server_eus 7.4 cpe:2.3:o:redhat:enterprise_linux_server_eus:7.4:*:*:*:*:*:*:*
redhat enterprise_linux_server_eus 7.5 cpe:2.3:o:redhat:enterprise_linux_server_eus:7.5:*:*:*:*:*:*:*
redhat enterprise_linux_server_eus 7.6 cpe:2.3:o:redhat:enterprise_linux_server_eus:7.6:*:*:*:*:*:*:*
redhat enterprise_linux_server_tus 7.3 cpe:2.3:o:redhat:enterprise_linux_server_tus:7.3:*:*:*:*:*:*:*
redhat enterprise_linux_server_tus 7.6 cpe:2.3:o:redhat:enterprise_linux_server_tus:7.6:*:*:*:*:*:*:*
redhat enterprise_linux_workstation 7.0 cpe:2.3:o:redhat:enterprise_linux_workstation:7.0:*:*:*:*:*:*:*

References for CVE-2015-3281

cvelogic Threat Intelligence