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Vulnerability details: VCID-aju4-13wq-j3az
Vulnerability ID VCID-aju4-13wq-j3az
Aliases CVE-2023-34462
GHSA-6mjq-h674-j845
Summary netty-handler SniHandler 16MB allocation ### Summary The `SniHandler` can allocate up to 16MB of heap for each channel during the TLS handshake. When the handler or the channel does not have an idle timeout, it can be used to make a TCP server using the `SniHandler` to allocate 16MB of heap. ### Details The `SniHandler` class is a handler that waits for the TLS handshake to configure a `SslHandler` according to the indicated server name by the `ClientHello` record. For this matter it allocates a `ByteBuf` using the value defined in the `ClientHello` record. Normally the value of the packet should be smaller than the handshake packet but there are not checks done here and the way the code is written, it is possible to craft a packet that makes the `SslClientHelloHandler` 1/ allocate a 16MB `ByteBuf` 2/ not fail `decode` method `in` buffer 3/ get out of the loop without an exception The combination of this without the use of a timeout makes easy to connect to a TCP server and allocate 16MB of heap memory per connection. ### Impact If the user has no idle timeout handler configured it might be possible for a remote peer to send a client hello packet which lead the server to buffer up to 16MB of data per connection. This could lead to a OutOfMemoryError and so result in a DDOS.
Status Published
Exploitability 0.5
Weighted Severity 6.2
Risk 3.1
Affected and Fixed Packages Package Details
Weaknesses (4)
CWE-400 Uncontrolled Resource Consumption
CWE-770 Allocation of Resources Without Limits or Throttling
CWE-1035 OWASP Top Ten 2017 Category A9 - Using Components with Known Vulnerabilities
CWE-937 OWASP Top Ten 2013 Category A9 - Using Components with Known Vulnerabilities
System Score Found at
cvssv3 6.5 https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2023-34462.json
epss 0.00416 https://api.first.org/data/v1/epss?cve=CVE-2023-34462
epss 0.00416 https://api.first.org/data/v1/epss?cve=CVE-2023-34462
epss 0.00416 https://api.first.org/data/v1/epss?cve=CVE-2023-34462
epss 0.00416 https://api.first.org/data/v1/epss?cve=CVE-2023-34462
epss 0.00416 https://api.first.org/data/v1/epss?cve=CVE-2023-34462
epss 0.00416 https://api.first.org/data/v1/epss?cve=CVE-2023-34462
epss 0.00519 https://api.first.org/data/v1/epss?cve=CVE-2023-34462
epss 0.00519 https://api.first.org/data/v1/epss?cve=CVE-2023-34462
epss 0.00519 https://api.first.org/data/v1/epss?cve=CVE-2023-34462
epss 0.00519 https://api.first.org/data/v1/epss?cve=CVE-2023-34462
epss 0.00519 https://api.first.org/data/v1/epss?cve=CVE-2023-34462
epss 0.00563 https://api.first.org/data/v1/epss?cve=CVE-2023-34462
epss 0.00563 https://api.first.org/data/v1/epss?cve=CVE-2023-34462
epss 0.00563 https://api.first.org/data/v1/epss?cve=CVE-2023-34462
cvssv3.1 6.5 https://ftp.suse.com/pub/projects/security/yaml/suse-cvss-scores.yaml
cvssv3.1_qr MODERATE https://github.com/advisories/GHSA-6mjq-h674-j845
cvssv3.1 6.5 https://github.com/netty/netty
generic_textual MODERATE https://github.com/netty/netty
cvssv3.1 6.5 https://github.com/netty/netty/commit/535da17e45201ae4278c0479e6162bb4127d4c32
generic_textual MODERATE https://github.com/netty/netty/commit/535da17e45201ae4278c0479e6162bb4127d4c32
ssvc Track https://github.com/netty/netty/commit/535da17e45201ae4278c0479e6162bb4127d4c32
cvssv3.1 6.5 https://github.com/netty/netty/security/advisories/GHSA-6mjq-h674-j845
cvssv3.1_qr MODERATE https://github.com/netty/netty/security/advisories/GHSA-6mjq-h674-j845
generic_textual MODERATE https://github.com/netty/netty/security/advisories/GHSA-6mjq-h674-j845
ssvc Track https://github.com/netty/netty/security/advisories/GHSA-6mjq-h674-j845
cvssv3.1 6.5 https://nvd.nist.gov/vuln/detail/CVE-2023-34462
generic_textual MODERATE https://nvd.nist.gov/vuln/detail/CVE-2023-34462
cvssv3.1 6.5 https://security.netapp.com/advisory/ntap-20230803-0001
generic_textual MODERATE https://security.netapp.com/advisory/ntap-20230803-0001
cvssv3.1 6.5 https://security.netapp.com/advisory/ntap-20230803-0001/
ssvc Track https://security.netapp.com/advisory/ntap-20230803-0001/
cvssv3.1 6.5 https://security.netapp.com/advisory/ntap-20240621-0007
generic_textual MODERATE https://security.netapp.com/advisory/ntap-20240621-0007
cvssv3.1 6.5 https://security.netapp.com/advisory/ntap-20240621-0007/
ssvc Track https://security.netapp.com/advisory/ntap-20240621-0007/
cvssv3.1 6.5 https://www.debian.org/security/2023/dsa-5558
generic_textual MODERATE https://www.debian.org/security/2023/dsa-5558
ssvc Track https://www.debian.org/security/2023/dsa-5558
Reference id Reference type URL
https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2023-34462.json
https://api.first.org/data/v1/epss?cve=CVE-2023-34462
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-34462
https://ftp.suse.com/pub/projects/security/yaml/suse-cvss-scores.yaml
https://github.com/netty/netty
https://github.com/netty/netty/commit/535da17e45201ae4278c0479e6162bb4127d4c32
https://github.com/netty/netty/security/advisories/GHSA-6mjq-h674-j845
https://nvd.nist.gov/vuln/detail/CVE-2023-34462
https://security.netapp.com/advisory/ntap-20230803-0001
https://security.netapp.com/advisory/ntap-20230803-0001/
https://security.netapp.com/advisory/ntap-20240621-0007
https://security.netapp.com/advisory/ntap-20240621-0007/
https://www.debian.org/security/2023/dsa-5558
1038947 https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1038947
2216888 https://bugzilla.redhat.com/show_bug.cgi?id=2216888
cpe:2.3:a:netty:netty:*:*:*:*:*:*:*:* https://nvd.nist.gov/vuln/search/results?adv_search=true&isCpeNameSearch=true&query=cpe:2.3:a:netty:netty:*:*:*:*:*:*:*:*
GHSA-6mjq-h674-j845 https://github.com/advisories/GHSA-6mjq-h674-j845
RHSA-2023:5165 https://access.redhat.com/errata/RHSA-2023:5165
RHSA-2023:5441 https://access.redhat.com/errata/RHSA-2023:5441
RHSA-2023:5946 https://access.redhat.com/errata/RHSA-2023:5946
RHSA-2023:7669 https://access.redhat.com/errata/RHSA-2023:7669
RHSA-2023:7697 https://access.redhat.com/errata/RHSA-2023:7697
RHSA-2024:0148 https://access.redhat.com/errata/RHSA-2024:0148
USN-6994-1 https://usn.ubuntu.com/6994-1/
No exploits are available.
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Found at https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2023-34462.json
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

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Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Found at https://ftp.suse.com/pub/projects/security/yaml/suse-cvss-scores.yaml
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

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Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Found at https://github.com/netty/netty
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

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Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Found at https://github.com/netty/netty/commit/535da17e45201ae4278c0479e6162bb4127d4c32
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

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Vector: SSVCv2/E:N/A:N/T:P/P:M/B:A/M:M/D:T/2024-07-16T18:36:13Z/ Found at https://github.com/netty/netty/commit/535da17e45201ae4278c0479e6162bb4127d4c32
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Found at https://github.com/netty/netty/security/advisories/GHSA-6mjq-h674-j845
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

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Vector: SSVCv2/E:N/A:N/T:P/P:M/B:A/M:M/D:T/2024-07-16T18:36:13Z/ Found at https://github.com/netty/netty/security/advisories/GHSA-6mjq-h674-j845
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Found at https://nvd.nist.gov/vuln/detail/CVE-2023-34462
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

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Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Found at https://security.netapp.com/advisory/ntap-20230803-0001
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

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Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Found at https://security.netapp.com/advisory/ntap-20230803-0001/
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

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Vector: SSVCv2/E:N/A:N/T:P/P:M/B:A/M:M/D:T/2024-07-16T18:36:13Z/ Found at https://security.netapp.com/advisory/ntap-20230803-0001/
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Found at https://security.netapp.com/advisory/ntap-20240621-0007
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

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physical

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Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Found at https://security.netapp.com/advisory/ntap-20240621-0007/
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

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Vector: SSVCv2/E:N/A:N/T:P/P:M/B:A/M:M/D:T/2024-07-16T18:36:13Z/ Found at https://security.netapp.com/advisory/ntap-20240621-0007/
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Found at https://www.debian.org/security/2023/dsa-5558
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

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Vector: SSVCv2/E:N/A:N/T:P/P:M/B:A/M:M/D:T/2024-07-16T18:36:13Z/ Found at https://www.debian.org/security/2023/dsa-5558
Exploit Prediction Scoring System (EPSS)
Percentile 0.60767
EPSS Score 0.00416
Published At June 30, 2025, 12:55 p.m.
Date Actor Action Source VulnerableCode Version
2025-07-01T12:15:56.929570+00:00 GithubOSV Importer Import https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2023/06/GHSA-6mjq-h674-j845/GHSA-6mjq-h674-j845.json 36.1.3