CVE-2025-12084VulnerabilityPublished 4 Feb 2026Updated 27 Jun 2026

Red Hat Security Advisory: python3.11 security update

Affects Red Hat python3.11Source GCVE Database

Mentioned vulnerabilities

CVE-2025-13836

Authoritative record:CVE-2025-12084· Medium 6.3

Not known to be exploited · CVSS 6.3 Medium.

Data as of 26 Oct 2026, 09:15 UTC

CVSS 4.0 base score

6.3Medium

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 0.7% chance of exploitation in 30 days – higher than 56% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N

Exploitation evidence

Disclosed: evidence found.
CVE published 3 Dec 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Affected software

Product	Affected	Fixed in
GitHubpython/cpython`pkg:github/python/cpython`Other threats	Affected =0 =3.11.0 =3.12.0 =3.13.0 =3.14.0 =3.15.0	Fixed in–

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

AI-suggested

Red Hat has released updated python3.12 packages for Red Hat Enterprise Linux 10.0 Extended Update Support and related CodeReady Linux Builder products that address these vulnerabilities. Users should apply the security update as described in the Red Hat advisory (RHSA-2026:2233) and the referenced article https://access.redhat.com/articles/11258. No alternative mitigations or workarounds are specified. Patch status is confirmed as fixed in the updated packages.

Description

Python is an interpreted, interactive, object-oriented programming language, which includes modules, classes, exceptions, very high level dynamic data types and dynamic typing. Python supports interfaces to many system calls and libraries, as well as to various windowing systems. Security Fix(es): * cpython: Excessive read buffering DoS in http.client (CVE-2025-13836) * cpython: python: cpython: Quadratic algorithm in xml.dom.minidom leads to denial of service (CVE-2025-12084) For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Impact

Successful exploitation of these vulnerabilities can cause denial of service by exhausting system resources due to excessive buffering or inefficient algorithmic complexity. This can disrupt applications or services relying on the affected Python modules. There is no indication of code execution or data compromise. No known exploits in the wild have been reported.

Summary

This advisory covers two vulnerabilities in the CPython implementation of Python 3.12. CVE-2025-13836 involves excessive read buffering in the http.client module that can lead to denial of service. CVE-2025-12084 involves a quadratic time complexity algorithm in xml.dom.minidom, which can also cause denial of service through resource exhaustion. Red Hat has released updated python3.12 packages for Red Hat Enterprise Linux 10.0 Extended Update Support and associated builder products to address these issues. The advisory references fixes tracked under Bugzilla entries BZ-2418078 and BZ-2418655. No CVSS scores are provided in the advisory, but the impact is rated moderate.

CWE-770Allocation of Resources Without Limits or Throttling (opens in a new tab)
Base weaknessLikelihood of exploit: HighCWE Top 25 (2025): #25
The product allocates a reusable resource or group of resources on behalf of an actor without imposing any intended restrictions on the size or number of resources that can be allocated.
Requirements
Clearly specify the minimum and maximum expectations for capabilities, and dictate which behaviors are acceptable when resource allocation reaches limits.
Architecture and Design
Limit the amount of resources that are accessible to unprivileged users. Set per-user limits for resources. Allow the system administrator to define these limits. Be careful to avoid CWE-410.
Architecture and Design
Design throttling mechanisms into the system architecture. The best protection is to limit the amount of resources that an unauthorized user can cause to be expended.
OWASP Cheat Sheets
Abuse Case (opens in a new tab)
OWASP ASVS 4.0.3
V8.1.4 (opens in a new tab)
V13.4.1 (opens in a new tab)
V11.1.4 (opens in a new tab)
Attack patterns
XML Ping of the Death (opens in a new tab)
Exponential Data Expansion (opens in a new tab)
Serialized Data Parameter Blowup (opens in a new tab)
Serialized Data with Nested Payloads (opens in a new tab)
Oversized Serialized Data Payloads (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

Community reviews

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 25 Jun 2026, 21:56 UTC

WeaknessesCWE-770

Technical details

References

Community reviews

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