WID-SEC-W-2023-1822
Vulnerability from csaf_certbund - Published: 2021-08-08 22:00 - Updated: 2023-07-19 22:00Es existiert eine Schwachstelle in Lynx bezüglich der "Server Name Indication" (SNI) Funktionalität im TLS Handshake. Wird Lynx mit einer URL aufgerufen, die Anmeldedaten enthält, so werden diese Informationen fälschlicherweise im SNI Teil des TLS Handshakes übertragen. Dies geschieht im Klartext, bevor Zertifikate geprüft wurden. Ein Angreifer, der einen Server kontrolliert oder sich in einer Man-in-the-middle Position befindet, kann diese Schwachstelle ausnutzen, um Informationen offenzulegen.
| Product | Identifier | Version | Remediation |
|---|---|---|---|
|
Debian Linux
Debian
|
cpe:/o:debian:debian_linux:-
|
— | |
|
Red Hat Enterprise Linux
Red Hat
|
cpe:/o:redhat:enterprise_linux:-
|
— | |
|
Open Source Arch Linux
Open Source
|
cpe:/o:archlinux:archlinux:-
|
— | |
|
Amazon Linux 2
Amazon
|
cpe:/o:amazon:linux_2:-
|
— |
{
"document": {
"aggregate_severity": {
"text": "mittel"
},
"category": "csaf_base",
"csaf_version": "2.0",
"distribution": {
"tlp": {
"label": "WHITE",
"url": "https://www.first.org/tlp/"
}
},
"lang": "de-DE",
"notes": [
{
"category": "legal_disclaimer",
"text": "Das BSI ist als Anbieter f\u00fcr die eigenen, zur Nutzung bereitgestellten Inhalte nach den allgemeinen Gesetzen verantwortlich. Nutzerinnen und Nutzer sind jedoch daf\u00fcr verantwortlich, die Verwendung und/oder die Umsetzung der mit den Inhalten bereitgestellten Informationen sorgf\u00e4ltig im Einzelfall zu pr\u00fcfen."
},
{
"category": "description",
"text": "Lynx ist ein textbasierter Web Browser, der f\u00fcr Unix- und Windows-Systeme verf\u00fcgbar ist.",
"title": "Produktbeschreibung"
},
{
"category": "summary",
"text": "Ein entfernter, anonymer Angreifer kann eine Schwachstelle in Lynx ausnutzen, um Informationen offenzulegen.",
"title": "Angriff"
},
{
"category": "general",
"text": "- UNIX\n- Linux\n- Windows\n- Sonstiges",
"title": "Betroffene Betriebssysteme"
}
],
"publisher": {
"category": "other",
"contact_details": "csaf-provider@cert-bund.de",
"name": "Bundesamt f\u00fcr Sicherheit in der Informationstechnik",
"namespace": "https://www.bsi.bund.de"
},
"references": [
{
"category": "self",
"summary": "WID-SEC-W-2023-1822 - CSAF Version",
"url": "https://wid.cert-bund.de/.well-known/csaf/white/2021/wid-sec-w-2023-1822.json"
},
{
"category": "self",
"summary": "WID-SEC-2023-1822 - Portal Version",
"url": "https://wid.cert-bund.de/portal/wid/securityadvisory?name=WID-SEC-2023-1822"
},
{
"category": "external",
"summary": "Amazon Linux Security Advisory ALAS-2023-2145 vom 2023-07-20",
"url": "https://alas.aws.amazon.com/AL2/ALAS-2023-2145.html"
},
{
"category": "external",
"summary": "OSS Mailing-list vom 2021-08-08",
"url": "http://seclists.org/oss-sec/2021/q3/78"
},
{
"category": "external",
"summary": "OSS Mailing-list vom 2021-08-08",
"url": "http://seclists.org/oss-sec/2021/q3/81"
},
{
"category": "external",
"summary": "Debian Security Advisory DLA-2736 vom 2021-08-09",
"url": "https://lists.debian.org/debian-lts-announce/2021/08/msg00010.html"
},
{
"category": "external",
"summary": "Arch Linux Security Advisory ASA-202108-9 vom 2021-08-10",
"url": "https://security.archlinux.org/ASA-202108-9"
},
{
"category": "external",
"summary": "Debian Security Advisory DSA-4953 vom 2021-08-10",
"url": "https://www.debian.org/security/2021/dsa-4953"
},
{
"category": "external",
"summary": "Red Hat Security Advisory RHSA-2022:2129 vom 2022-05-10",
"url": "https://access.redhat.com/errata/RHSA-2022:2129"
}
],
"source_lang": "en-US",
"title": "Lynx: Schwachstelle erm\u00f6glicht Offenlegung von Informationen",
"tracking": {
"current_release_date": "2023-07-19T22:00:00.000+00:00",
"generator": {
"date": "2024-08-15T17:55:55.745+00:00",
"engine": {
"name": "BSI-WID",
"version": "1.3.5"
}
},
"id": "WID-SEC-W-2023-1822",
"initial_release_date": "2021-08-08T22:00:00.000+00:00",
"revision_history": [
{
"date": "2021-08-08T22:00:00.000+00:00",
"number": "1",
"summary": "Initiale Fassung"
},
{
"date": "2021-08-09T22:00:00.000+00:00",
"number": "2",
"summary": "Neue Updates von Debian aufgenommen"
},
{
"date": "2021-08-31T22:00:00.000+00:00",
"number": "3",
"summary": "Referenz(en) aufgenommen: FEDORA-2021-232161E4D5, FEDORA-2021-57287BD052, FEDORA-2021-F59BDA7D94"
},
{
"date": "2022-05-10T22:00:00.000+00:00",
"number": "4",
"summary": "Neue Updates von Red Hat aufgenommen"
},
{
"date": "2023-07-19T22:00:00.000+00:00",
"number": "5",
"summary": "Neue Updates von Amazon aufgenommen"
}
],
"status": "final",
"version": "5"
}
},
"product_tree": {
"branches": [
{
"branches": [
{
"category": "product_name",
"name": "Amazon Linux 2",
"product": {
"name": "Amazon Linux 2",
"product_id": "398363",
"product_identification_helper": {
"cpe": "cpe:/o:amazon:linux_2:-"
}
}
}
],
"category": "vendor",
"name": "Amazon"
},
{
"branches": [
{
"category": "product_name",
"name": "Debian Linux",
"product": {
"name": "Debian Linux",
"product_id": "2951",
"product_identification_helper": {
"cpe": "cpe:/o:debian:debian_linux:-"
}
}
}
],
"category": "vendor",
"name": "Debian"
},
{
"branches": [
{
"category": "product_name",
"name": "Open Source Arch Linux",
"product": {
"name": "Open Source Arch Linux",
"product_id": "T013312",
"product_identification_helper": {
"cpe": "cpe:/o:archlinux:archlinux:-"
}
}
},
{
"category": "product_name",
"name": "Open Source Lynx \u003c 2.9.0dev.9",
"product": {
"name": "Open Source Lynx \u003c 2.9.0dev.9",
"product_id": "T020055",
"product_identification_helper": {
"cpe": "cpe:/a:lynx:lynx:2.9.0dev.9"
}
}
}
],
"category": "vendor",
"name": "Open Source"
},
{
"branches": [
{
"category": "product_name",
"name": "Red Hat Enterprise Linux",
"product": {
"name": "Red Hat Enterprise Linux",
"product_id": "67646",
"product_identification_helper": {
"cpe": "cpe:/o:redhat:enterprise_linux:-"
}
}
}
],
"category": "vendor",
"name": "Red Hat"
}
]
},
"vulnerabilities": [
{
"cve": "CVE-2021-38165",
"notes": [
{
"category": "description",
"text": "Es existiert eine Schwachstelle in Lynx bez\u00fcglich der \"Server Name Indication\" (SNI) Funktionalit\u00e4t im TLS Handshake. Wird Lynx mit einer URL aufgerufen, die Anmeldedaten enth\u00e4lt, so werden diese Informationen f\u00e4lschlicherweise im SNI Teil des TLS Handshakes \u00fcbertragen. Dies geschieht im Klartext, bevor Zertifikate gepr\u00fcft wurden. Ein Angreifer, der einen Server kontrolliert oder sich in einer Man-in-the-middle Position befindet, kann diese Schwachstelle ausnutzen, um Informationen offenzulegen."
}
],
"product_status": {
"known_affected": [
"2951",
"67646",
"T013312",
"398363"
]
},
"release_date": "2021-08-08T22:00:00.000+00:00",
"title": "CVE-2021-38165"
}
]
}
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Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
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Vulnerability timeline
Sightings and recorded dates, grouped by day · UTC
How durations are calculated
Following the VTEM framework (Black Hat USA 2015), time to patch starts when the vendor or a coordinator was informed, total time to patch at discovery, and disclosure to patch at public disclosure; vendor response time runs from the report to its acknowledgement. Time to exploit and time unpatched start at the earliest discovery or report, falling back to public disclosure. Unpatched time ends at the first recorded patch, or the calculation time when no patch is recorded. Exploitation to patch shows the interval between those two events; a published proof of concept is a public exploit, not exploitation.
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