[UPDATE] [medium] Python: Multiple vulnerabilities

mediumCVE-2021-3737 CVE-2021-4189

A remote, anonymous attacker can exploit multiple vulnerabilities in Python to conduct a denial of service attack and disclose information.

CSIRTS triage

vendor: Python product: Python Denial of service Information disclosure

What: Multiple vulnerabilities can be exploited by a remote anonymous attacker to conduct denial of service attacks and disclose information.
Who is affected: All deployments using affected versions of Python are at risk.
Urgency: Remediation is medium urgency as the vulnerabilities are not currently exploited but could lead to denial of service or information disclosure.
Action: Update Python to the latest version to mitigate these vulnerabilities.

AI-assisted analysis generated from the source advisory — verify against the original.

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Details

Source: CERT-Bund (BSI) Security Advisories (DE · national-cert · site)
Severity: medium
Published: 2026-08-20
Exploitation: Not in CISA KEV at last sync
Language: Machine-translated to English — verify against the original

Original advisory: https://wid.cert-bund.de/portal/wid/securityadvisory?name=WID-SEC-2022-0011

Exploitation outlook

EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.

Elevated exploitation riskCVE-2021-373711.6% 30-day exploitation probability — well above the norm. Schedule remediation this cycle. Riskier than 96% of all EPSS-scored CVEs.
Moderate exploitation riskCVE-2021-41893.2% 30-day exploitation probability. Patch within normal cadence, watch for KEV listing. Riskier than 87% of all EPSS-scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2021-3737	coverage & exploitation status	NVD · CVE.org
CVE-2021-4189	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.

high[NEW] [high] Oracle Solaris third-party components: Multiple vulnerabilitiescert-bund
unknownUSN-8509-1: Python vulnerabilitiesubuntu

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A cluster of recent advisories against the same product widens the attack surface — attackers routinely chain freshly published CVEs on one product, so review these together.

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