CVE-2023-45539

HAProxy before 2.8.2 accepts # as part of the URI component, which might allow remote attackers to obtain sensitive information or have unspecified other impact upon misinterpretation of a path_end rule, such as routing index.html#.png to a static server.

Published: 2023-11-28 Last update: 2026-06-17 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2023-45539 is rated Moderate Risk (59.2/100): CVSS High severity, with medium exploitation likelihood (EPSS 1.51%). EPSS rose +1.49% 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-2023-45539

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 0.02% 1.51% +1.49%
2 2025-03-30 0.07% 0.02% -0.05%
3 2025-03-29 — 0.07% —

Full EPSS history (7 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2023-45539

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
8.2 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
 3.9 4.2 [email protected]
8.2 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
 3.9 4.2 134c704f-9b21-4f2e-91b3-4a467353bcc0

Weakness enumeration for CVE-2023-45539

OS Trackers for CVE-2023-45539

vendor priority summary link
alpine — CVE-2023-45539: 1 source package rows (haproxy); 7 state rows across 7 repos (3.17-main, 3.18-main, 3.19-main, 3.20-main, 3.21-main, 3.22-main, edge-main); fixed 0, open 7. https://security.alpinelinux.org/vuln/CVE-2023-45539
debian not yet assigned CVE-2023-45539 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-2023-45539
redhat medium — https://access.redhat.com/security/cve/CVE-2023-45539
suse medium — https://www.suse.com/security/cve/CVE-2023-45539/
ubuntu medium CVE-2023-45539 medium priority: Ubuntu including 1 source packages (haproxy), 9 status rows across 9 suites (bionic, focal, jammy, lunar, mantic, noble, trusty, upstream, xenial): released 6, not-affected 2, ignored 1. https://ubuntu.com/security/CVE-2023-45539

Affected software / configurations for CVE-2023-45539

Vendor Product Version Raw CPE
haproxy haproxy < 2.8.2 cpe:2.3:a:haproxy:haproxy:*:*:*:*:*:*:*:*

References for CVE-2023-45539

cvelogic Threat Intelligence