CVE-2026-40562
📛 CVE Title
Gazelle versions through 0.49 for Perl allows HTTP Request Smuggling via Improper Header Precedence
Description
Gazelle versions through 0.49 for Perl allows HTTP Request Smuggling via Improper Header Precedence. Gazelle incorrectly prioritizes "Content-Length" over "Transfer-Encoding: chunked" when both headers are present in an HTTP request. Per RFC 7230 3.3.3, Transfer-Encoding must take precedence. An attacker could exploit this to smuggle malicious HTTP requests via a front-end reverse proxy.
Overview
- State
- PUBLISHED
- Assigner (CNA)
- CPANSec
- CVSS severity
- high
- CVSS score
- 7.5 / 10
- CVSS vector
AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N- Effective score
- 7.5 / 10 HIGH source: CNA overview
- CWE(s)
-
CWE-444 - Reserved
- 2026-04-14
- Published
- 2026-05-06 14:36 UTC
- Last updated
- 2026-05-07 18:13 UTC
- Source
- https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/40xxx/CVE-2026-40562.json
- Linked Threat
- CVE-2026-40562 — CVE-2026-40562
NVD triage scoring NVD CVE 2.0
Layer NVD adds on top of the CNA's CVE record — published / last-modified timestamps, exploitability / impact subscores, and the FIRST.org EPSS probability that this CVE will be exploited in the wild in the next 30 days.
- NVD published
- 2026-05-06 13:16:09 UTC
- NVD last modified
- 2026-05-11 15:04:24 UTC
- NVD CVSS v3.1
- 7.5 / 10 HIGH source: 134c704f-9b21-4f2e-91b3-4a467353bcc0
- NVD CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N- Exploitability subscore
- 3.9 / 10
- Impact subscore
- 3.6 / 10
- EPSS score
- 0.0004 (probability of exploitation in next 30 days)
- EPSS percentile
- 11.53% vs all CVEs — higher = more likely to be exploited, as of 2026-05-24
NVD / KEV / EPSS data refreshed 2026-05-25 10:55 UTC. Re-run the 🛰 Backfill from NVD button above to refresh.
European Union Vulnerability Database ENISA EUVD
ENISA's official EU repository for curated vulnerability intelligence. Carries a separate identifier (EUVD-YYYY-NNNN) and frequently exposes an earlier-published description + CVSS than NVD does.
- EUVD ID
-
EUVD-2026-27825 - Assigner
- CPANSec
- Published
- May 6, 2026, 12:36:34 PM
- Updated
- May 7, 2026, 4:13:49 PM
- EUVD base score (CVSS 3.1)
-
7.5 / 10
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N - EUVD-reported EPSS
- 0.0400
- Vendors
- KAZEBURO
- Products
-
Gazelle (0 ≤0.49)
ENISA description: Gazelle versions through 0.49 for Perl allows HTTP Request Smuggling via Improper Header Precedence. Gazelle incorrectly prioritizes "Content-Length" over "Transfer-Encoding: chunked" when both headers are present in an HTTP request. Per RFC 7230 3.3.3, Transfer-Encoding must take precedence. An attacker could exploit this to smuggle malicious HTTP requests via a front-end reverse proxy.
Affected products (1)
| Vendor | Product | Versions | Platforms |
|---|---|---|---|
| KAZEBURO | Gazelle |
0 (affected)
|
— |
Affected products — CPE 2.3 (1) NVD
NVD's normalized CPE 2.3 matchers, used by vendor tools (vulnerability scanners, asset managers) for automated detection. Compare with the CNA's free-text "Affected products" section above.
cpe:2.3:a:kazeburo:gazelle:*:*:*:*:*:perl:*:*
Vendor references (3)
References embedded in the original CVE record by the assigning CNA.
MITRE references (3) cveawg.mitre.org
Pulled from MITRE's CVE Services API by the 🛰 Backfill from MITRE button.
Web references (4)
DuckDuckGo results ranked by threat-intel / vendor advisory domains. Generated by the 🔎 Find references (web) button above — same flow as the Remediations search.
- https://nvd.nist.gov/vuln/detail/CVE-2026-40562 tenable:nvd.nist.gov
- http://www.openwall.com/lists/oss-security/2026/05/06/7 tenable:www.openwall.com
- https://www.cve.org/CVERecord?id=CVE-2026-40562 tenable:www.cve.org
- https://www.first.org/epss/ tenable:www.first.org
NVD-tagged references (4)
Reference list NVD curates from the CNA record, vendor advisories, and third-party reports. The tag chips below are NVD's analyst-assigned categories.
- http://www.openwall.com/lists/oss-security/2026/05/06/7 af854a3a-2127-422b-91ae-364da2661108 Mailing ListThird Party Advisory
- https://datatracker.ietf.org/doc/html/rfc7230#section-3.3.3 9b29abf9-4ab0-4765-b253-1875cd9b441e Third Party Advisory
- https://metacpan.org/release/KAZEBURO/Gazelle-0.50/changes 9b29abf9-4ab0-4765-b253-1875cd9b441e Release Notes
- https://security.metacpan.org/patches/G/Gazelle/0.49/CVE-2026-40562-r1.patch 9b29abf9-4ab0-4765-b253-1875cd9b441e Patch
Remediations (18)
Remediations are stored against the linked Threat row; the list below is deduplicated across both pages.
-
web:cyberpress.org
The U.S. Cybersecurity and Infrastructure Security Agency (CISA) has added two actively exploited Microsoft Defender vulnerabilities to its Known Exploited Vulnerabilities (KEV) catalog, issuing an urgent remediation directive for federal agencies with a due date of June 3, 2026 .
2026-05-23 21:11 UTC -
web:cybersecuritynews.com
Microsoft's May 2026 Patch Tuesday lands with a heavy enterprise focus, fixing 120 vulnerabilities across Windows, Office, Azure, developer tools, and Microsoft 365 apps, including 29 remote code execution (RCE) flaws rated Critical.
2026-05-23 21:11 UTC -
web:krebsonsecurity.com
Microsoft expects that exploitation is more likely. May's Patch Tuesday is a welcome respite from April, which saw Microsoft fix a near-record 167 security flaws.
2026-05-23 21:11 UTC -
web:portal.msrc.microsoft.com
The Security Update Guide provides information on the latest Microsoft security updates, helping users understand and address potential vulnerabilities effectively.
2026-05-23 21:11 UTC -
web:securereading.com
Microsoft has released its May 2026 Patch Tuesday security updates addressing multiple critical vulnerabilities affecting enterprise cloud services, operating systems, virtualization infrastructure, authentication platforms, and business applications.
2026-05-23 21:11 UTC -
web:www.bleepingcomputer.com
Microsoft has released out-of-band (OOB) security updates to patch a critical ASP.NET Core privilege escalation vulnerability.
2026-05-23 21:11 UTC -
web:www.cisecurity.org
<p>Multiple vulnerabilities have been discovered in Microsoft products, the most severe of which could allow for remote code execution. Successful exploitation of the most severe of these vulnerabilities could result in an attacker gaining the same privileges as the logged-on user. Depending on the privileges associated with the user, an attacker could then install programs; view, change, or ...
2026-05-23 21:11 UTC -
web:www.helpnetsecurity.com
Microsoft has marked May 2026 Patch Tuesday by releasing fixes for 120+ CVE -numbered vulnerabilities, none of which are actively exploited.
2026-05-23 21:11 UTC -
web:www.oracle.com
This Critical Patch Update contains 481 new security patches across the product families listed below. Please note that an MOS note summarizing the content of this Critical Patch Update and other Oracle Software Security Assurance activities is located at April 2026 Critical Patch Update: Executive Summary and Analysis.
2026-05-23 21:11 UTC -
web:zecurit.com
Get the complete breakdown of Microsoft's May 2026 Patch Tuesday. We analyze the latest security updates and all critical CVEs .
2026-05-23 21:11 UTC -
web:krebsonsecurity.com
For a clickable, per- patch breakdown, check out the SANS Internet Storm Center Patch Tuesday roundup. Running into problems applying any of these updates?
2026-05-26 02:47 UTC -
web:securityboulevard.com
Cybersecurity vulnerabilities pose significant risks to organizations in today's digital landscape. Left unaddressed, these vulnerabilities can lead to data breaches, financial losses, and reputational damage. Organizations must decide how to tackle vulnerabilities—through remediation , mitigation , or a combination of both. But which strategy is more effective? This blog explores the ...
2026-05-26 02:47 UTC -
web:translate.google.com
Google's service, offered free of charge, instantly translates words, phrases, and web pages between English and over 100 other languages.
2026-05-26 02:47 UTC -
web:www.bugcrowd.com
Vulnerability mitigation is typically considered a temporary or interim solution. While mitigation measures can reduce the immediate risk associated with vulnerabilities, they may not provide a permanent fix . Organizations should aim to prioritize and plan for complete vulnerability remediation whenever feasible and allocate resources accordingly.
2026-05-26 02:47 UTC -
web:www.lansweeper.com
Which vulnerabilities, issues, and other things did Microsoft update? Discover what's new using Lansweeper's Patch Tuesday May 2026 summary.
2026-05-26 02:47 UTC -
web:www.secure.com
Learn the difference between vulnerability remediation and mitigation , and how a risk-based strategy can strengthen your security posture.
2026-05-26 02:47 UTC -
web:www.virustotal.com
VirusTotal is a platform for scanning files and URLs for viruses, malware, and other threats using multiple antivirus engines.
2026-05-26 02:47 UTC -
web:www.zafran.io
Mitigation is the control implemented or the action taken to reduce the impact or likelihood of a vulnerability or exposure being exploited before a fix is available or applied. Remediation is the resolution of the vulnerability or exposure which is completed typically through applying patches, updates, or correcting misconfigurations.
2026-05-26 02:47 UTC
AI Forensic Analysis
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Raw JSON
The full cvelistV5 record. Download as CVE-2026-40562.json.
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