CVE-2021-28662: debian debian_linux Improper Encoding or Escaping of Output
CVSS: 6.5v3.1MediumModified
AliasesALPINE-CVE-2021-28662UBUNTU-CVE-2021-28662DEBIAN-CVE-2021-28662
Published 27-05-2021Last modified 03-08-2024
Vulnerability summary
CVE-2021-28662 is a medium (CVSS 6.5) Improper Encoding or Escaping of Output vulnerability in debian debian_linux. EPSS estimates a 71.76% chance of exploitation in the next 30 days, higher than 99.4% of scored vulnerabilities.
CVSS score
6.5/10
010
Medium · v3.1 (NVD)EPSS score
71.76%
0%100%
Critical · 0.00 pp in 30 daysKEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded
Advisory lineage
Upstream 0 · Downstream 9 · Related 6Timeline
- 27-05-2021PublishedVulnerability first disclosed.
- 03-08-2024Last modifiedVulnerability information updated.
Description
An issue was discovered in Squid 4.x before 4.15 and 5.x before 5.0.6. If a remote server sends a certain response header over HTTP or HTTPS, there is a denial of service. This header can plausibly occur in benign network traffic.
CVSS metrics
5 scores · 4 sources · 2 versionsMedium 6.5Preferred score · NVD (NIST)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:HSourcesAll 4 agree
- OSV · AlpineEcosystem advisory · calculated6.5MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
- OSV · UbuntuEcosystem advisory · calculated6.5MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
- OSV · DebianEcosystem advisory · calculated6.5MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
Medium 4.3Preferred score · NVD (NIST)
AV:N/AC:M/Au:N/C:N/I:N/A:PSourcesSingle source
EPSS trend
Probability
71.76%
Chance of exploitation in the next 30 days
Percentile
99%
Versus all other CVEs
30-day change
0.00 pp
From 71.76% on 18-09-2026
18-09-202618-10-2026
EPSS score71.76%
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Debian2 products
- squid< 4.13-10
- debian_linuxEOL10.0
Alpine1 product
- squid≥ 4.0.1, < 4.15-r0 | ≥ 4.0.1, < 5.0.6-r0
Fedoraproject1 product
- fedoraEOL33 | 34
Squid-cache1 product
- squid≥ 4.0.1, < 4.15 | ≥ 5.0, < 5.0.6
Ubuntu1 product
- squid< 4.10-1ubuntu1.4
5 vendors · 6 products
References
13 links- github.com/squid-cache/squid/commit/051824924c709bd6162a378f746fb859454c674ePatchThird Party Advisory
- lists.fedoraproject.org/archives/…Vendor Advisory
- lists.fedoraproject.org/archives/…Vendor Advisory