CVE-2021-28662

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Source
https://cve.org/CVERecord?id=CVE-2021-28662
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-28662.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2021-28662
Downstream
Related
Published
2021-05-27T12:15:08.263Z
Modified
2026-04-16T04:32:30.382774755Z
Severity
  • 6.5 (Medium) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H CVSS Calculator
Summary
[none]
Details

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.

References

Affected packages

Git / github.com/squid-cache/squid

Affected ranges

Type
GIT
Repo
https://github.com/squid-cache/squid
Events
Introduced
1243ec712bf76c549ba7f48fcdc30d98ce550449
Fixed
648729b05673c6166c5d91c6ee4cda30cc164839
Introduced
0 Unknown introduced commit / All previous commits are affected
Fixed
1521895e24671463bf590cabcdbd2acf637ed2c1
Introduced
0 Unknown introduced commit / All previous commits are affected
Last affected
0f67e2aac4a27d0c5ffbfa1dcd89d8abbc7175a7
Fixed
051824924c709bd6162a378f746fb859454c674e
Database specific 
{
    "versions": [
        {
            "introduced": "4.0.1"
        },
        {
            "fixed": "4.15"
        },
        {
            "introduced": "5.0"
        },
        {
            "fixed": "5.0.6"
        },
        {
            "introduced": "0"
        },
        {
            "last_affected": "33"
        }
    ]
}

Affected versions

Other
M-staged-PR161
M-staged-PR164
M-staged-PR170
M-staged-PR176
M-staged-PR179
M-staged-PR181
M-staged-PR182
M-staged-PR186
M-staged-PR189
M-staged-PR193
M-staged-PR195
M-staged-PR196
M-staged-PR198
M-staged-PR199
M-staged-PR200
M-staged-PR202
M-staged-PR206
M-staged-PR208
M-staged-PR209
M-staged-PR210
M-staged-PR218
M-staged-PR220
M-staged-PR221
M-staged-PR225
M-staged-PR227
M-staged-PR229
M-staged-PR230
M-staged-PR235
M-staged-PR237
M-staged-PR238
M-staged-PR239
M-staged-PR241
M-staged-PR242
M-staged-PR252
M-staged-PR255
M-staged-PR258
M-staged-PR264
M-staged-PR266
M-staged-PR267
M-staged-PR268
M-staged-PR274
M-staged-PR276
M-staged-PR293
M-staged-PR294
M-staged-PR295
M-staged-PR299
M-staged-PR306
M-staged-PR314
M-staged-PR319
M-staged-PR330
M-staged-PR342
M-staged-PR345
M-staged-PR348
M-staged-PR351
M-staged-PR359
M-staged-PR364
M-staged-PR365
M-staged-PR366
M-staged-PR370
M-staged-PR372
M-staged-PR373
M-staged-PR375
M-staged-PR376
SQUID_3_5_27
SQUID_4_0_1
SQUID_4_0_10
SQUID_4_0_11
SQUID_4_0_12
SQUID_4_0_13
SQUID_4_0_14
SQUID_4_0_15
SQUID_4_0_16
SQUID_4_0_17
SQUID_4_0_18
SQUID_4_0_19
SQUID_4_0_2
SQUID_4_0_20
SQUID_4_0_21
SQUID_4_0_22
SQUID_4_0_23
SQUID_4_0_24
SQUID_4_0_25
SQUID_4_0_3
SQUID_4_0_4
SQUID_4_0_5
SQUID_4_0_6
SQUID_4_0_7
SQUID_4_0_8
SQUID_4_0_9
SQUID_4_1
SQUID_4_10
SQUID_4_11
SQUID_4_12
SQUID_4_13
SQUID_4_14
SQUID_4_2
SQUID_4_3
SQUID_4_4
SQUID_4_5
SQUID_4_6
SQUID_4_7
SQUID_4_8
SQUID_4_9
SQUID_5_0_1
SQUID_5_0_2
SQUID_5_0_3
SQUID_5_0_4
SQUID_5_0_5

Database specific

vanir_signatures_modified 
"2026-04-11T17:12:16Z"
vanir_signatures 
[
    {
        "id": "CVE-2021-28662-ac67f9e9",
        "signature_version": "v1",
        "digest": {
            "line_hashes": [
                "246787021619791419152269128153398552627",
                "137540088876487517479355767659710642705",
                "2037448173086037427154046699180625686",
                "111963318781500401476263553951823657637"
            ],
            "threshold": 0.9
        },
        "source": "https://github.com/squid-cache/squid/commit/051824924c709bd6162a378f746fb859454c674e",
        "deprecated": false,
        "target": {
            "file": "src/http/RegisteredHeaders.cc"
        },
        "signature_type": "Line"
    },
    {
        "id": "CVE-2021-28662-b5ea6bf5",
        "signature_version": "v1",
        "deprecated": false,
        "source": "https://github.com/squid-cache/squid/commit/051824924c709bd6162a378f746fb859454c674e",
        "digest": {
            "function_hash": "213594514490356346423760141520931754203",
            "length": 211.0
        },
        "target": {
            "function": "HeaderLookupTable_t::lookup",
            "file": "src/http/RegisteredHeaders.cc"
        },
        "signature_type": "Function"
    }
]
source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-28662.json"
unresolved_ranges 
[
    {
        "events": [
            {
                "introduced": "0"
            },
            {
                "last_affected": "10.0"
            }
        ]
    },
    {
        "events": [
            {
                "introduced": "0"
            },
            {
                "last_affected": "34"
            }
        ]
    }
]