HTTP/2 HPACK integer overflow and buffer allocation (CVE-2023-36478)
Published Sources: BSI, Debian, SUSE, CVE.org, OSV
What is affected, what to do
Eclipse Jetty provides a web server and servlet container. In versions 11.0.0 through 11.0.15, 10.0.0 through 10.0.15, and 9.0.0 through 9.4.52, an integer overflow in `MetaDataBuilder.checkSize` allows for HTTP/2 HPACK header values to exceed their size limit. `MetaDataBuilder.java` determines if a header name or value exceeds the size limit, and throws an exception if the limit is exceeded.
An exploit is publicly available. Update jetty to version 9.4.53, jenkins to version 2.414.3.
- Affected
- Eclipse Foundation Jetty.project
gte 9.3.0, < 9.4.53..*
- Eclipse Foundation Jetty.project
Not sure whether and how you are affected? Ask a question about this vulnerability
Metrics
7.5
Priority
XIEM Effective CVSS: highest available CVSS rating from NVD and vendor data.
Source: NVD, CVSS v3
7.5
CVSS v3
Severity High on the scale from 0 to 10.
Source: BSI, Debian, SUSE, CVE.org, OSV
4.8 %
EPSS score
Moderate — model estimates 1-10% exploitation likelihood.
Source: FIRST EPSS, percentile 91.9
Show all metrics
- Severity
- High
Priority (0–325)
The priority score is a consolidated metric that condenses several individual signals into a single, action-guiding ranking: technical severity (CVSS), exploitation likelihood (EPSS), known-exploited status (KEV) and the context of the affected asset. The aim is to answer the only truly important question in vulnerability management: what first?
Read in glossary- 108.73 Methodology
Exploit maturity
An exploit is code or a technique that specifically uses a concrete vulnerability to force unintended behaviour — such as executing code or escalating privileges. It is the tool that turns a theoretical flaw into a practical attack.
Read in glossary- PoC (publicly reported)
XIEM Effective CVSS
XIEM® is the tiered managed-security operating model from NEOSEC and a registered trademark of NEOSEC GmbH. It extends classic SIEM — the central collection, normalisation and correlation of security-relevant events — with endpoint forensics, network visibility and deception technology, and consolidates them into three building tiers: Sentry, Orchestrate and Command.
Read in glossary- 7.5 Methodology
CVSS v3
CVSS is the globally established, open standard for assessing the technical severity of a vulnerability on a scale from 0 to 10. It describes how easily a flaw can be exploited and what damage it can cause — but not how likely its actual exploitation is. CVSS and the complementary EPSS deliberately answer different questions.
Read in glossary- 7.5
EPSS score
The EPSS score is the absolute model output for an individual vulnerability: the estimated probability of real-world exploitation within the next 30 days, expressed as a value between 0 and 1 (i.e. 0 % to 100 %). A score of 0.42 means „the model estimates a 42 % chance of real-world exploitation within 30 days“.
Read in glossary- 4.8 %
- Moderate — model estimates 1-10% exploitation likelihood.
EPSS percentile
The EPSS percentile is the relative position of a vulnerability within all EPSS-scored CVEs, expressed as a value between 0 and 1. A percentile of 0.90 means „this CVE has a higher EPSS score than 90 % of all other scored CVEs“. Unlike the EPSS score, it is not a probability — but a positioning within a ranking.
Read in glossary- 91.9
- Critical — this CVE ranks in the top fifth of all CVEs scored today (rank ≥ 80%).
KEV status
The KEV catalogue is a list maintained by the US authority CISA of vulnerabilities for which active exploitation in the wild has been confirmed. It answers not the question „how severe?“ but „is it already being attacked?“ — thereby sharply prioritising patching.
Read in glossary- —
- Published
CWE
CWE is a catalogue of typical weakness types in software and hardware — such as flawed input validation, unsafe memory handling or poor authentication. Where a CVE names a concrete vulnerability in a concrete product, a CWE describes the underlying class of defect.
Read in glossary- CWE-190, CWE-400
Detection rules
No NEOSEC detection rule is available for this vulnerability yet.
Classification under NIS2 and CRA
Rule-based classification from exploitation status and severity. It does not replace a case-by-case assessment.
NIS2
NIS2 is EU Directive (EU) 2022/2555 to raise the level of cybersecurity across the Union. It substantially broadens obligations compared with the first NIS directive: more sectors, mandatory risk management, staged reporting duties and personal accountability of senior management.
Read in glossary- High technical severity: assess and remediate the vulnerability in vulnerability handling under Art. 21(2)(e) NIS2 and document the decision.
CRA
The CRA is EU Regulation (EU) 2024/2847 setting horizontal cybersecurity requirements for „products with digital elements“ — from industrial controllers and software to connected consumer devices. For the first time manufacturers must ensure security across the entire product lifecycle, handle vulnerabilities and provide security updates.
Read in glossary- From 11.12.2027, Annex I Part II CRA requires manufacturers of affected products with digital elements to handle vulnerabilities without delay and provide security updates.
ISO/IEC 27001
ISO/IEC 27001 is the internationally leading standard for an information security management system (ISMS). It describes a risk-based, process-oriented framework to systematically plan, implement, review and improve information security.
Read in glossary- Control A.8.8, management of technical vulnerabilities: assess relevance to your systems, plan remediation and keep evidence.
Description
Eclipse Jetty provides a web server and servlet container. In versions 11.0.0 through 11.0.15, 10.0.0 through 10.0.15, and 9.0.0 through 9.4.52, an integer overflow in `MetaDataBuilder.checkSize` allows for HTTP/2 HPACK header values to exceed their size limit. `MetaDataBuilder.java` determines if a header name or value exceeds the size limit, and throws an exception if the limit is exceeded. However, when length is very large and huffman is true, the multiplication by 4 in line 295 will overflow, and length will become negative. `(_size+length)` will now be negative, and the check on line 296 will not be triggered. Furthermore, `MetaDataBuilder.checkSize` allows for user-entered HPACK header value sizes to be negative, potentially leading to a very large buffer allocation later on when the user-entered size is multiplied by 2. This means that if a user provides a negative length value (or, more precisely, a length value which, when multiplied by the 4/3 fudge factor, is negative), and this length value is a very large positive number when multiplied by 2, then the user can cause a very large buffer to be allocated on the server. Users of HTTP/2 can be impacted by a remote denial of service attack. The issue has been fixed in versions 11.0.16, 10.0.16, and 9.4.53. There are no known workarounds.
Source: BSI CSAF, BSI WID Portal, Debian Security Advisories, suse_csaf, NVD (NIST), OSV (Open Source Vulnerabilities), cvelistv5
Affected products
The following versions are affected. Older releases of the same product line are also vulnerable unless stated otherwise.
| Affected versions | Fixed in | ||
|---|---|---|---|
| eclipse | jetty.project |
|
|
| eclipse | jetty |
|
|
| jenkins | jenkins |
|
|
| maven | org.eclipse.jetty.http2:http2-hpack |
|
|
Vendors and products
Affected operating systems
| Linux | debian | debian_linux | 10.0 |
| Linux | debian | debian_linux | 11.0 |
| Linux | debian | debian_linux | 12.0 |
| Linux | debian | jetty9 | bookworm |
| Linux | debian | jetty9 | bullseye |
Weakness classes (CWE)
CWE-190Integer Overflow or Wraparound
Base
The product performs a calculation that can produce an integer overflow or wraparound when the logic assumes that the resulting value will always be larger than the original value. This occurs when an integer value is incremented to a value that is too large to store in the associated representation. When this occurs, the value may become a very small or negative number.
Entry at MITRE CWE-190CWE-400Uncontrolled Resource Consumption
Class
The product does not properly control the allocation and maintenance of a limited resource.
Entry at MITRE CWE-400
Public exploit references
Publicly reported proof-of-concepts, exploit modules and detection templates for this vulnerability. NEOSEC links to the original sources only and does not provide any exploit code.
| Reference tagged as exploit | github.com (opens in a new tab) | PoC (publicly reported)reported, not verified | — |
References & sources
- github.comeclipse/jetty.project/security/advisories/GHSA-wgh7-54f2-x98rweb, x_refsource_CONFIRM, Exploit, Vendor advisory
- github.comjetty/jetty.project/security/advisories/GHSA-wgh7-54f2-x98rweb
- NVD (NIST)vuln/detail/CVE-2023-36478advisory
- github.comeclipse/jetty.project/pull/9634web, x_refsource_MISC, Issue tracking, Patch
- github.comeclipse/jetty.projectpackage
- github.comeclipse/jetty.project/releases/tag/jetty-10.0.16web, x_refsource_MISC, Release notes
- github.comeclipse/jetty.project/releases/tag/jetty-11.0.16web, x_refsource_MISC, Release notes
- github.comeclipse/jetty.project/releases/tag/jetty-9.4.53.v20231009web, x_refsource_MISC, Release notes
- lists.debian.orgdebian-lts-announce/2023/10/msg00045.htmlweb, Mailing list
- security.netapp.comadvisory/ntap-20231116-0011web
- security.netapp.comadvisory/ntap-20240621-0006web
- debian.orgsecurity/2023/dsa-5540web, Third-party advisory
- openwall.comlists/oss-security/2023/10/18/4web, Mailing list, Third-party advisory
- security.netapp.comadvisory/ntap-20231116-0011Third-party advisory
- security.netapp.comadvisory/ntap-20240621-0006
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<a href="https://intel.neosec.eu/en/cve/CVE-2023-36478"><img src="https://intel.neosec.eu/badge/cve/CVE-2023-36478.svg?lang=en" alt="CVE-2023-36478 – NEOSEC Intel" height="20"></a>