CVE-2021-33503

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Source
https://cve.org/CVERecord?id=CVE-2021-33503
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-33503.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2021-33503
Aliases
Downstream
AZL (1)
CGA (4)
CLSA (2)
DEBIAN (1)
MGASA (2)
MINI (1)
OESA (3)
openSUSE (4)
RHSA (5)
RLSA (2)
ROOT (1)
SUSE (5)
UBUNTU (1)
Related
ALSA (2)
openSUSE (4)
SUSE (5)
Published
2021-06-29T11:15:07Z
Modified
2026-08-07T11:49:15Z
Severity
  • 7.5 (High) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H CVSS Calculator
Summary
[none]
Details

An issue was discovered in urllib3 before 1.26.5. When provided with a URL containing many @ characters in the authority component, the authority regular expression exhibits catastrophic backtracking, causing a denial of service if a URL were passed as a parameter or redirected to via an HTTP redirect.

Database specific 
{
    "unresolved_ranges":  [
        {
            "cpes":  [
                "cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*",
                "cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*"
            ],
            "extracted_events":  [
                {
                    "introduced":  "33"
                },
                {
                    "last_affected":  "33"
                },
                {
                    "introduced":  "34"
                },
                {
                    "last_affected":  "34"
                }
            ],
            "source":  "CPE_STRING",
            "vendor_product":  "fedoraproject:fedora"
        },
        {
            "cpes":  [
                "cpe:2.3:a:oracle:enterprise_manager_ops_center:12.4.0.0:*:*:*:*:*:*:*"
            ],
            "extracted_events":  [
                {
                    "introduced":  "12.4.0.0"
                },
                {
                    "last_affected":  "12.4.0.0"
                }
            ],
            "source":  "CPE_STRING",
            "vendor_product":  "oracle:enterprise_manager_ops_center"
        },
        {
            "cpes":  [
                "cpe:2.3:a:oracle:instantis_enterprisetrack:17.1:*:*:*:*:*:*:*",
                "cpe:2.3:a:oracle:instantis_enterprisetrack:17.2:*:*:*:*:*:*:*",
                "cpe:2.3:a:oracle:instantis_enterprisetrack:17.3:*:*:*:*:*:*:*"
            ],
            "extracted_events":  [
                {
                    "introduced":  "17.1"
                },
                {
                    "last_affected":  "17.1"
                },
                {
                    "introduced":  "17.2"
                },
                {
                    "last_affected":  "17.2"
                },
                {
                    "introduced":  "17.3"
                },
                {
                    "last_affected":  "17.3"
                }
            ],
            "source":  "CPE_STRING",
            "vendor_product":  "oracle:instantis_enterprisetrack"
        },
        {
            "cpes":  [
                "cpe:2.3:a:oracle:zfs_storage_appliance_kit:8.8:*:*:*:*:*:*:*"
            ],
            "extracted_events":  [
                {
                    "introduced":  "8.8"
                },
                {
                    "last_affected":  "8.8"
                }
            ],
            "source":  "CPE_STRING",
            "vendor_product":  "oracle:zfs_storage_appliance_kit"
        }
    ]
}
References

Affected packages

Git / github.com/urllib3/urllib3

Affected ranges

Type
GIT
Repo
https://github.com/urllib3/urllib3
Events
Introduced
7e856c04723036934fe314c63701466e4f42d2ee
Fixed
d1616473df94b94f0f5ad19d2a6608cfe93b7cdf
Fixed
2d4a3fee6de2fa45eb82169361918f759269b4ec
Database specific
Show details 
{
    "cpe":  "cpe:2.3:a:python:urllib3:*:*:*:*:*:*:*:*",
    "extracted_events":  [
        {
            "introduced":  "1.25.4"
        },
        {
            "fixed":  "1.26.5"
        }
    ],
    "source":  [
        "CPE_RANGE",
        "REFERENCES"
    ]
}

Affected versions

1.*
1.25.4
1.25.5
1.25.6
1.25.7
1.25.8
1.26.0
1.26.1
1.26.2
1.26.3
1.26.4

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-33503.json"