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 outg
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
- Jul 6, 2015
- Updated
- Jun 16, 2026
- EPSS
- 4.3% · 91th percentile
- CWE
- CWE-119
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Report tools
Action score
21
Monitor
Low priority for now.
- CVSS
- 20 / 40 · 5.0 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 1 / 30 · 4.3%
Affected systems
| Vendor | Product | CPE |
|---|---|---|
| haproxy | haproxy | cpe:2.3:a:haproxy:haproxy |
| debian | debian linux | cpe:2.3:o:debian:debian_linux |
| canonical | ubuntu linux | cpe:2.3:o:canonical:ubuntu_linux |
| opensuse | openstack cloud | cpe:2.3:o:opensuse:openstack_cloud |
| opensuse | opensuse | cpe:2.3:o:opensuse:opensuse |
| suse | linux enterprise high availability extension | cpe:2.3:o:suse:linux_enterprise_high_availability_extension |
| redhat | enterprise linux desktop | cpe:2.3:o:redhat:enterprise_linux_desktop |
| redhat | enterprise linux server | cpe:2.3:o:redhat:enterprise_linux_server |
| redhat | enterprise linux server aus | cpe:2.3:o:redhat:enterprise_linux_server_aus |
| redhat | enterprise linux server eus | cpe:2.3:o:redhat:enterprise_linux_server_eus |
| redhat | enterprise linux server tus | cpe:2.3:o:redhat:enterprise_linux_server_tus |
| redhat | enterprise linux workstation | cpe:2.3:o:redhat:enterprise_linux_workstation |
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- canonical ubuntu linux14.10
- canonical ubuntu linux15.04
- debian debian linux8.0
- haproxy haproxy1.5
- haproxy haproxy1.5.0
- haproxy haproxy1.5.1
- haproxy haproxy1.5.10
- haproxy haproxy1.5.11
- haproxy haproxy1.5.12
- haproxy haproxy1.5.13
- haproxy haproxy1.5.2
- haproxy haproxy1.5.3
- haproxy haproxy1.5.4
- haproxy haproxy1.5.5
- haproxy haproxy1.5.6
- haproxy haproxy1.5.7
- haproxy haproxy1.5.8
- haproxy haproxy1.5.9
- haproxy haproxy1.6
- opensuse openstack cloud5
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| Debian:12 | haproxy | before 1.5.14-1 | 1.5.14-1 |
| Debian:8 | haproxy | before 1.5.8-3+deb8u1 | 1.5.8-3+deb8u1 |
| openSUSE:Tumbleweed | haproxy | before 1.7.0-1.1 | 1.7.0-1.1 |
| Red Hat:enterprise_linux:6::server | haproxy | before 0:1.5.4-2.el6_7.1 | 0:1.5.4-2.el6_7.1 |
| Red Hat:enterprise_linux:6::server | haproxy-debuginfo | before 0:1.5.4-2.el6_7.1 | 0:1.5.4-2.el6_7.1 |
| Red Hat:enterprise_linux:7::server | haproxy | before 0:1.5.4-4.el7_1.1 | 0:1.5.4-4.el7_1.1 |
| Red Hat:enterprise_linux:7::server | haproxy-debuginfo | before 0:1.5.4-4.el7_1.1 | 0:1.5.4-4.el7_1.1 |
| Red Hat:openshift:2.0::el6 | haproxy15side | before 0:1.5.4-2.el6op | 0:1.5.4-2.el6op |
| Red Hat:openshift:2.0::el6 | haproxy15side-debuginfo | before 0:1.5.4-2.el6op | 0:1.5.4-2.el6op |
| Red Hat:openshift:2.0::el6 | openshift-enterprise-release | before 0:2.2.8-1.el6op | 0:2.2.8-1.el6op |
| Red Hat:openshift:2.0::el6 | openshift-enterprise-upgrade | before 0:2.2.8-1.el6op | 0:2.2.8-1.el6op |
| Red Hat:openshift:2.0::el6 | openshift-enterprise-upgrade-broker | before 0:2.2.8-1.el6op | 0:2.2.8-1.el6op |
| Red Hat:openshift:2.0::el6 | openshift-enterprise-upgrade-node | before 0:2.2.8-1.el6op | 0:2.2.8-1.el6op |
| Red Hat:openshift:2.0::el6 | openshift-enterprise-yum-validator | before 0:2.2.8-1.el6op | 0:2.2.8-1.el6op |
| Red Hat:openshift:2.0::el6 | openshift-origin-broker-util | before 0:1.37.4.2-1.el6op | 0:1.37.4.2-1.el6op |
| Red Hat:openshift:2.0::el6 | openshift-origin-cartridge-haproxy | before 0:1.31.4.1-1.el6op | 0:1.31.4.1-1.el6op |
| Red Hat:openshift:2.0::el6 | openshift-origin-cartridge-jbosseap | before 0:2.27.3.1-1.el6op | 0:2.27.3.1-1.el6op |
| Red Hat:openshift:2.0::el6 | openshift-origin-cartridge-jbossews | before 0:1.35.3.2-1.el6op | 0:1.35.3.2-1.el6op |
| Red Hat:openshift:2.0::el6 | openshift-origin-cartridge-python | before 0:1.34.1.1-1.el6op | 0:1.34.1.1-1.el6op |
| Red Hat:openshift:2.0::el6 | openshift-origin-node-util | before 0:1.38.5.1-1.el6op | 0:1.38.5.1-1.el6op |
| Red Hat:openshift:2.0::el6 | rhc | before 0:1.38.4.5-1.el6op | 0:1.38.4.5-1.el6op |
| Red Hat:openshift:2.0::el6 | rubygem-openshift-origin-common | before 0:1.29.4.1-1.el6op | 0:1.29.4.1-1.el6op |
| Red Hat:openshift:2.0::el6 | rubygem-openshift-origin-controller | before 0:1.38.4.2-1.el6op | 0:1.38.4.2-1.el6op |
| Red Hat:openshift:2.0::el6 | rubygem-openshift-origin-node | before 0:1.38.4.1-1.el6op | 0:1.38.4.1-1.el6op |
+3
Same product
haproxy: all recordsOther highest-scoring records for the same primary product.
- CVE-2020-11100In hpack_dht_insert in hpack-tbl.c in the HPACK decoder in HAProxy 1.8 through 2.x before 2.1.4, a remote attacker can write arbitrary bytes53Plan
- CVE-2019-14241HAProxy through 2.0.2 allows attackers to cause a denial of service (ha_panic) via vectors related to htx_manage_client_side_cookies in prot51Plan
- CVE-2021-40346An integer overflow exists in HAProxy 2.0 through 2.5 in htx_add_header that can be exploited to perform an HTTP request smuggling attack, a47Plan
- CVE-2016-5360HAproxy 1.6.x before 1.6.6, when a deny comes from a reqdeny rule, allows remote attackers to cause a denial of service (uninitialized memor43Plan
- CVE-2019-19330The HTTP/2 implementation in HAProxy before 2.0.10 mishandles headers, as demonstrated by carriage return (CR, ASCII 0xd), line feed (LF, AS40Plan
- CVE-2023-25725HAProxy before 2.7.3 may allow a bypass of access control because HTTP/1 headers are inadvertently lost in some situations, aka "request smu38Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| debian:haproxy | 1.5.14-1 · Debian:12 | Package registry (OSV) |
| opensuse:haproxy | 1.7.0-1.1 · openSUSE:Tumbleweed | Package registry (OSV) |
| red hat:haproxy | 0:1.5.4-2.el6_7.1 · Red Hat:enterprise_linux:6::server | Package registry (OSV) |
| red hat:haproxy-debuginfo | 0:1.5.4-2.el6_7.1 · Red Hat:enterprise_linux:6::server | Package registry (OSV) |
| red hat:openshift-enterprise-release | 0:2.2.8-1.el6op · Red Hat:openshift:2.0::el6 | Package registry (OSV) |
| red hat:openshift-enterprise-upgrade | 0:2.2.8-1.el6op · Red Hat:openshift:2.0::el6 | Package registry (OSV) |
| red hat:openshift-enterprise-upgrade-broker | 0:2.2.8-1.el6op · Red Hat:openshift:2.0::el6 | Package registry (OSV) |
| red hat:openshift-enterprise-yum-validator | 0:2.2.8-1.el6op · Red Hat:openshift:2.0::el6 | Package registry (OSV) |
| red hat:openshift-origin-broker-util | 0:1.37.4.2-1.el6op · Red Hat:openshift:2.0::el6 | Package registry (OSV) |
| red hat:openshift-origin-cartridge-jbosseap | 0:2.27.3.1-1.el6op · Red Hat:openshift:2.0::el6 | Package registry (OSV) |
| red hat:rhc | 0:1.38.4.5-1.el6op · Red Hat:openshift:2.0::el6 | Package registry (OSV) |
| red hat:rubygem-openshift-origin-common | 0:1.29.4.1-1.el6op · Red Hat:openshift:2.0::el6 | Package registry (OSV) |
| red hat:rubygem-openshift-origin-controller | 0:1.38.4.2-1.el6op · Red Hat:openshift:2.0::el6 | Package registry (OSV) |
| red hat:rubygem-openshift-origin-routing-daemon | 0:0.26.4.4-1.el6op · Red Hat:openshift:2.0::el6 | Package registry (OSV) |
| suse:haproxy | 1.5.4-2.4.1 · SUSE:Linux Enterprise High Availability Extension 12 | Package registry (OSV) |
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
No dated events beyond publication.
FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
No commit or PR link among the references.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
No credits in the CNA record.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
No nightly-computed relations.
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
—
Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
Technical details
Attack conditions
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- P · data can be read
- Integrity
- none
- Availability
- none
- Attack complexity
- Low
- Confidentiality impact
- P
- Integrity impact
- None
- Availability impact
- None
Weakness class (CWE)
CWE-119 · Improper Restriction of Operations within the Bounds of a Memory BufferCVSS vector
AV:N/AC:L/Au:N/C:P/I:N/A:N
nvd-primary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
Attack patterns (CAPEC)
- Buffer Overflow via Environment VariablesCAPEC-10likelihood: High · High
- Overflow BuffersCAPEC-100likelihood: High · Very High
- Buffer ManipulationCAPEC-123likelihood: High · Very High
- Client-side Injection-induced Buffer OverflowCAPEC-14likelihood: Medium · High
- Filter Failure through Buffer OverflowCAPEC-24likelihood: High · High
- MIME ConversionCAPEC-42likelihood: High · High
- Overflow Binary Resource FileCAPEC-44likelihood: High · Very High
- Buffer Overflow via Symbolic LinksCAPEC-45likelihood: High · High
ATT&CK techniques
—
Noroxi analysis
No Noroxi analysis for this record yet
We don't hand-write analysis for all 385,000+ vulnerabilities; that wouldn't be honest. For notable, high-impact vulnerabilities our team writes the mechanism, detection and remediation steps.
We use this product, ask for helpChange log
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
- git.haproxy.org/?p=haproxy-1.5.git%3Ba=commit%3Bh=7ec765568883b2d4e5a2796adbeb492a22ec9bd4
- lists.opensuse.org/opensuse-security-announce/2015-10/msg00001.html
- lists.opensuse.org/opensuse-security-announce/2015-10/msg00023.html
- rhn.redhat.com/errata/RHSA-2015-1741.html
- rhn.redhat.com/errata/RHSA-2015-2666.html
- www.debian.org/security/2015/dsa-3301
- www.haproxy.org/news.html
- www.securityfocus.com/bid/75554
- www.ubuntu.com/usn/USN-2668-1
Vendor advisories and official records. Exploit/PoC links are deliberately left out.