CVE-2026-18503

See a problem?
Please try reporting it to the source first.
Source
https://cve.org/CVERecord?id=CVE-2026-18503
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-18503.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-18503
Aliases
Published
2026-08-10T13:45:31.618Z
Modified
2026-08-12T04:15:36.485100907Z
Severity
  • 2.4 (Low) CVSS_V4 - CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N CVSS Calculator
Summary
Super-linear CPU usage for unbounded input to csv.Sniffer.sniff()
Details

Attacker-controlled CSV samples can trigger super-linear regular-expression work during dialect sniffing and consume significant CPU when applications pass unbounded input to csv.Sniffer.sniff().

Database specific 
{
    "cwe_ids": [
        "CWE-1176"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/18xxx/CVE-2026-18503.json",
    "cna_assigner": "PSF"
}
References

Affected packages

Git / github.com/python/cpython

Affected ranges

Type
GIT
Repo
https://github.com/python/cpython
Events
Introduced
0 Unknown introduced commit / All previous commits are affected
Introduced
ebf955df7a89ed0c7968f79faec1de49f61ed7cb
Introduced
f31a89bb901067dd105b00cfa90523cf7ffdbbdd
Fixed
4061bc4c35f7c26f25264666d4ba083b93d2f6f9
Fixed
823f0323ee6ec1402088b73bce1a38473cac36dc
Fixed
37e98da7c19a9e5892ee756d6dee08225422cd49
Fixed
063d4555c94ef412c731527dbf30193327f2ee82
Fixed
476fb09cdb0d73e645849d98c610e7e5697ce7c9
Fixed
89f29c760c02774b099ddd6863268eb13fa3946a
Fixed
b30c7fa9edd921a118f286e9f90f560777fa693b
Database specific
Show details 
{
    "source": [
        "AFFECTED_FIELD",
        "REFERENCES"
    ],
    "extracted_events": [
        {
            "introduced": "0"
        },
        {
            "fixed": "3.13.15"
        },
        {
            "introduced": "3.14.0"
        },
        {
            "fixed": "3.14.7"
        },
        {
            "introduced": "3.15.0a1"
        },
        {
            "fixed": "3.15.0rc1"
        }
    ]
}

Affected versions

v0.*
v0.9.8
v0.9.9
v1.*
v1.0.1
v1.0.2
v1.1
v1.1.1
v1.2
v1.2b1
v1.2b2
v1.2b3
v1.2b4
v1.3
v1.3b1
v1.4
v1.4b1
v1.4b2
v1.4b3
v1.5
v1.5.1
v1.5.2
v1.5.2a1
v1.5.2a2
v1.5.2b1
v1.5.2b2
v1.5.2c1
v1.5a1
v1.5a2
v1.5a3
v1.5a4
v1.5b1
v1.5b2
v1.6a1
v1.6a2
v2.*
v2.0
v2.0b1
v2.0b2
v2.0c1
v2.1
v2.1a1
v2.1a2
v2.1b1
v2.1b2
v2.1c1
v2.1c2
v2.2a3
v2.3c1
v2.3c2
v2.4
v2.4a1
v2.4a2
v2.4a3
v2.4b1
v2.4b2
v2.4c1
v3.*
v3.0a1
v3.0a2
v3.0a3
v3.0a4
v3.0a5
v3.0b1
v3.0b2
v3.0b3
v3.0rc1
v3.0rc2
v3.0rc3
v3.1
v3.10.0a1
v3.10.0a7
v3.11.0a3
v3.11.0a4
v3.11.0a5
v3.11.0a6
v3.11.0a7
v3.11.0b1
v3.12.0
v3.12.0a1
v3.12.0a2
v3.12.0a3
v3.12.0a4
v3.12.0a5
v3.12.0a6
v3.12.0a7
v3.12.0b1
v3.12.0b2
v3.12.0b3
v3.12.0b4
v3.12.0rc1
v3.12.0rc2
v3.12.0rc3
v3.12.1
v3.12.10
v3.12.11
v3.12.12
v3.12.13
v3.12.2
v3.12.3
v3.12.4
v3.12.5
v3.12.6
v3.12.7
v3.12.8
v3.12.9
v3.13.0
v3.13.0a1
v3.13.0a2
v3.13.0a3
v3.13.0a4
v3.13.0a5
v3.13.0a6
v3.13.0b1
v3.13.0b2
v3.13.0b3
v3.13.0b4
v3.13.0rc1
v3.13.0rc2
v3.13.0rc3
v3.13.1
v3.13.10
v3.13.11
v3.13.12
v3.13.13
v3.13.14
v3.13.2
v3.13.3
v3.13.4
v3.13.5
v3.13.6
v3.13.7
v3.13.8
v3.14.0
v3.14.1
v3.14.2
v3.14.3
v3.14.4
v3.14.5
v3.14.5rc1
v3.14.6
v3.15.0b1
v3.15.0b2
v3.15.0b3
v3.15.0b4
v3.1a1
v3.1a2
v3.1b1
v3.1rc1
v3.1rc2
v3.2a1
v3.2a2
v3.2a3
v3.2a4
v3.2b1
v3.2b2
v3.2rc1
v3.2rc2
v3.2rc3
v3.3.0a2
v3.3.0a3
v3.3.0a4
v3.3.0b1
v3.3.0b2
v3.3.0rc1
v3.3.0rc2
v3.3.0rc3
v3.4.0a1
v3.4.0a2
v3.4.0a3
v3.4.0a4
v3.4.0b1
v3.4.0b2
v3.4.0b3
v3.5.0a1
v3.5.0a2
v3.5.0a3
v3.5.0a4
v3.5.0b1
v3.6.0a3
v3.6.0b1
v3.7.0a2
v3.9.0a2

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-18503.json"