CVE-2021-38165

Name: CVE-2021-38165
Creator: NVD / NIST
Published: 2021-08-07T18:15:06.997+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 5.3/10EPSS 4.46%

Last modified Jun 17, 2026

CVE-2021-38165 is a medium-severity vulnerability rated 5.3/10 on the CVSS scale. Lynx through 2.8.9 mishandles the userinfo subcomponent of a URI, which allows remote attackers to discover cleartext credentials because they may appear in SNI data.. EPSS estimates a 4.46% chance of exploitation in the next 30 days.

Description

Lynx through 2.8.9 mishandles the userinfo subcomponent of a URI, which allows remote attackers to discover cleartext credentials because they may appear in SNI data.

Metrics

CVSS 3.1

5.3/10

CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:N/A:N

EPSS Probability

4.46%

90.2th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-522

Affected Software

Vendor	Product	Versions
Lynx Project	Lynx	<= 2.8.9
Debian	Debian Linux	9.0
Debian	Debian Linux	10.0
Fedoraproject	Fedora	33
Fedoraproject	Fedora	34
Fedoraproject	Fedora	35

References

http://www.openwall.com/lists/oss-security/2021/08/07/11Mailing List, Third Party Advisory
http://www.openwall.com/lists/oss-security/2021/08/07/12Mailing List, Third Party Advisory
http://www.openwall.com/lists/oss-security/2021/08/07/9Mailing List, Third Party Advisory
https://bugs.debian.org/991971Issue Tracking, Third Party Advisory
https://github.com/w3c/libwww/blob/f010b4cc58d32f34b162f0084fe093f7097a61f0/Library/src/HTParse.c#L118Third Party Advisory
https://lists.debian.org/debian-lts-announce/2021/08/msg00010.htmlMailing List, Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/7YMUHFJJWTZ6HBHTYXVDPNZINGGURHDW/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/K6PZF7JNTFCOJ62HXZG4Q2NEHSZ6IO2V/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/VKNK7GQBJBUBMJVNKVC7RTCYWUYMFJQW/
https://lynx.invisible-island.net/current/CHANGES.htmlRelease Notes, Third Party Advisory
https://www.debian.org/security/2021/dsa-4953Third Party Advisory
https://www.openwall.com/lists/oss-security/2021/08/07/1Mailing List, Third Party Advisory
https://www.openwall.com/lists/oss-security/2021/08/07/11Mailing List
http://www.openwall.com/lists/oss-security/2021/08/07/11Mailing List, Third Party Advisory
http://www.openwall.com/lists/oss-security/2021/08/07/12Mailing List, Third Party Advisory
http://www.openwall.com/lists/oss-security/2021/08/07/9Mailing List, Third Party Advisory
https://bugs.debian.org/991971Issue Tracking, Third Party Advisory
https://github.com/w3c/libwww/blob/f010b4cc58d32f34b162f0084fe093f7097a61f0/Library/src/HTParse.c#L118Third Party Advisory
https://lists.debian.org/debian-lts-announce/2021/08/msg00010.htmlMailing List, Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/7YMUHFJJWTZ6HBHTYXVDPNZINGGURHDW/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/K6PZF7JNTFCOJ62HXZG4Q2NEHSZ6IO2V/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/VKNK7GQBJBUBMJVNKVC7RTCYWUYMFJQW/
https://lynx.invisible-island.net/current/CHANGES.htmlRelease Notes, Third Party Advisory
https://www.debian.org/security/2021/dsa-4953Third Party Advisory
https://www.openwall.com/lists/oss-security/2021/08/07/1Mailing List, Third Party Advisory
https://www.openwall.com/lists/oss-security/2021/08/07/11Mailing List

Timeline

Published: Aug 7, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-38165?

Lynx through 2.8.9 mishandles the userinfo subcomponent of a URI, which allows remote attackers to discover cleartext credentials because they may appear in SNI data.

How severe is CVE-2021-38165?

CVE-2021-38165 has a CVSS score of 5.3/10 (MEDIUM severity). The EPSS model estimates a 4.46% probability of exploitation in the next 30 days.

How do I fix CVE-2021-38165?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-38165?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST