Vulnerability-Lookup

ALSA-2021:4161

Vulnerability from osv_almalinux – Published: 2021-11-09 08:26 – Updated: 2021-11-12 10:20 – Source website

Summary

Moderate: python-jinja2 security update

Details

The python-jinja2 package contains Jinja2, a template engine written in pure Python. Jinja2 provides a Django inspired non-XML syntax but supports inline expressions and an optional sandboxed environment.

Security Fix(es):

python-jinja2: ReDoS vulnerability due to the sub-pattern (CVE-2020-28493)

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.

Additional Changes:

For detailed information on changes in this release, see the AlmaLinux Release Notes linked from the References section.

References

URL

Type

	https://errata.almalinux.org/8/ALSA-2021-4161.html	ADVISORY
	https://vulners.com/cve/CVE-2020-28493	REPORT

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "AlmaLinux:8",
        "name": "python3-jinja2"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.10.1-3.el8"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "details": "The python-jinja2 package contains Jinja2, a template engine written in pure Python. Jinja2 provides a Django inspired non-XML syntax but supports inline expressions and an optional sandboxed environment. \n\nSecurity Fix(es):\n\n* python-jinja2: ReDoS vulnerability due to the sub-pattern (CVE-2020-28493)\n\nFor 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.\n\nAdditional Changes:\n\nFor detailed information on changes in this release, see the AlmaLinux Release Notes linked from the References section.",
  "id": "ALSA-2021:4161",
  "modified": "2021-11-12T10:20:56Z",
  "published": "2021-11-09T08:26:43Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://errata.almalinux.org/8/ALSA-2021-4161.html"
    },
    {
      "type": "REPORT",
      "url": "https://vulners.com/cve/CVE-2020-28493"
    }
  ],
  "related": [
    "CVE-2020-28493"
  ],
  "summary": "Moderate: python-jinja2 security update"
}

CVE-2020-28493 (GCVE-0-2020-28493)

Vulnerability from cvelistv5 – Published: 2021-02-01 19:30 – Updated: 2024-09-16 17:24

Title

Regular Expression Denial of Service (ReDoS)

Summary

This affects the package jinja2 from 0.0.0 and before 2.11.3. The ReDoS vulnerability is mainly due to the `_punctuation_re regex` operator and its use of multiple wildcards. The last wildcard is the most exploitable as it searches for trailing punctuation. This issue can be mitigated by Markdown to format user content instead of the urlize filter, or by implementing request timeouts and limiting process memory.

Severity

5.3 (Medium)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L/E:P

CWE

Regular Expression Denial of Service (ReDoS)

Assigner

snyk mitre root

References

5 references

URL	Tags
https://snyk.io/vuln/SNYK-PYTHON-JINJA2-1012994	x_refsource_MISC
https://github.com/pallets/jinja/blob/ab81fd9c277…	x_refsource_MISC
https://github.com/pallets/jinja/pull/1343	x_refsource_MISC
https://lists.fedoraproject.org/archives/list/pac…	vendor-advisoryx_refsource_FEDORA
https://security.gentoo.org/glsa/202107-19	vendor-advisoryx_refsource_GENTOO

Impacted products

1 product

Vendor	Product	Version
n/a	jinja2	Affected: 0.0.0 , < unspecified (custom) Affected: unspecified , < 2.11.3 (custom)

Date Public

2021-02-01 00:00

Credits

Yeting Li

Show details on NVD website

JSON

To clipboard

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Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.