Protocol vs scheme mismatch

published 2022-08-10 4 y ago modified 2026-06-17 4 mo ago also EUVD-2021-23724

cvss: 4.2; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 2.3%; EPSS 2.3% chance of exploitation in 30 days, percentile 83%
public exploits: 0; none known

Improper Input Validation vulnerability in header parsing of Apache Traffic Server allows an attacker to request secure resources. This issue affects Apache Traffic Server 8.0.0 to 9.1.2.

Patch / fix

distros 1

trafficserver Debian 12 9.1.3+ds-1

debian advisories DEBIAN-CVE-2021-37150

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: partial
Assessed: 14 mo ago (2025-09-08)

Exploit prediction

2.25% chance of exploitation in the next 30 days, higher than 83% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CISA ADP	3.1	4.2	CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:N
NVD	3.1	7.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
CNA	3.1	4.2	CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:N

Affected products

Apache Software Foundation Apache Traffic Server

Classification

Weakness

CWE-20 Improper Input Validation

References

debian.org /security/2022/dsa-5206
vendor-advisory, third-party-advisory
lists.fedoraproject.org /archives/list/package-announce%40lists.fedoraproject.org/message/CJ67IWD5PRJUOIYIDJRUG3UMS2UF4X4J/
vendor-advisory
lists.fedoraproject.org /archives/list/package-announce%40lists.fedoraproject.org/message/ZCSBQBYPOZSWS5LCOAQ6LJLRLXFIAW5A/
vendor-advisory
lists.apache.org /thread/rc64lwbdgrkv674koc3zl1sljr9vwg21
mailing-list, vendor-advisory
lists.debian.org /debian-lts-announce/2023/01/msg00019.html
mailing-list, third-party-advisory

Sources

CVE List CVE-2021-37150
NVD CVE-2021-37150

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary