Vulnerability-Lookup

CNVD-2021-13240

Vulnerability from cnvd - Published: 2021-02-27

Title

GNU Screen拒绝服务漏洞（CNVD-2021-13240）

Description

GNU Screen是一款由GNU计划开发的用于命令行终端切换的自由软件。用户可以通过该软件同时连接多个本地或远程的命令行会话，并在其间自由切换。 GNU Screen 4.8.0及更早版本中的encoding.c存在拒绝服务漏洞。攻击者可通过特制UTF-8字符序列利用该漏洞导致无效写访问和应用程序崩溃。

Severity

高

Formal description

厂商尚未提供漏洞修复方案，请关注厂商主页更新： https://ftp.gnu.org/gnu/screen/

Reference

https://nvd.nist.gov/vuln/detail/CVE-2021-26937

Impacted products

Name
Gnu Screen <=4.8.0

Show details on source website

JSON

To clipboard

{
  "cves": {
    "cve": {
      "cveNumber": "CVE-2021-26937",
      "cveUrl": "https://nvd.nist.gov/vuln/detail/CVE-2021-26937"
    }
  },
  "description": "GNU Screen\u662f\u4e00\u6b3e\u7531GNU\u8ba1\u5212\u5f00\u53d1\u7684\u7528\u4e8e\u547d\u4ee4\u884c\u7ec8\u7aef\u5207\u6362\u7684\u81ea\u7531\u8f6f\u4ef6\u3002\u7528\u6237\u53ef\u4ee5\u901a\u8fc7\u8be5\u8f6f\u4ef6\u540c\u65f6\u8fde\u63a5\u591a\u4e2a\u672c\u5730\u6216\u8fdc\u7a0b\u7684\u547d\u4ee4\u884c\u4f1a\u8bdd\uff0c\u5e76\u5728\u5176\u95f4\u81ea\u7531\u5207\u6362\u3002\n\nGNU Screen 4.8.0\u53ca\u66f4\u65e9\u7248\u672c\u4e2d\u7684encoding.c\u5b58\u5728\u62d2\u7edd\u670d\u52a1\u6f0f\u6d1e\u3002\u653b\u51fb\u8005\u53ef\u901a\u8fc7\u7279\u5236UTF-8\u5b57\u7b26\u5e8f\u5217\u5229\u7528\u8be5\u6f0f\u6d1e\u5bfc\u81f4\u65e0\u6548\u5199\u8bbf\u95ee\u548c\u5e94\u7528\u7a0b\u5e8f\u5d29\u6e83\u3002",
  "formalWay": "\u5382\u5546\u5c1a\u672a\u63d0\u4f9b\u6f0f\u6d1e\u4fee\u590d\u65b9\u6848\uff0c\u8bf7\u5173\u6ce8\u5382\u5546\u4e3b\u9875\u66f4\u65b0\uff1a\r\nhttps://ftp.gnu.org/gnu/screen/",
  "isEvent": "\u901a\u7528\u8f6f\u786c\u4ef6\u6f0f\u6d1e",
  "number": "CNVD-2021-13240",
  "openTime": "2021-02-27",
  "products": {
    "product": "Gnu Screen \u003c=4.8.0"
  },
  "referenceLink": "https://nvd.nist.gov/vuln/detail/CVE-2021-26937",
  "serverity": "\u9ad8",
  "submitTime": "2021-02-10",
  "title": "GNU Screen\u62d2\u7edd\u670d\u52a1\u6f0f\u6d1e\uff08CNVD-2021-13240\uff09"
}

CVE-2021-26937 (GCVE-0-2021-26937)

Vulnerability from cvelistv5 – Published: 2021-02-09 19:35 – Updated: 2025-05-09 20:03

Summary

encoding.c in GNU Screen through 4.8.0 allows remote attackers to cause a denial of service (invalid write access and application crash) or possibly have unspecified other impact via a crafted UTF-8 character sequence.

Severity

No CVSS data available.

CWE

Assigner

mitre CNA under the mitre root

CNA scorecard E 28/100 over 2325 records in the last 180 days details

References

10 references

URL	Tags
https://lists.gnu.org/archive/html/screen-devel/2…	x_refsource_MISC
https://www.openwall.com/lists/oss-security/2021/…	x_refsource_MISC
https://ftp.gnu.org/gnu/screen/	x_refsource_MISC
http://www.openwall.com/lists/oss-security/2021/02/09/8	mailing-listx_refsource_MLIST
https://lists.debian.org/debian-lts-announce/2021…	mailing-listx_refsource_MLIST
https://www.debian.org/security/2021/dsa-4861	vendor-advisoryx_refsource_DEBIAN
https://lists.fedoraproject.org/archives/list/pac…	vendor-advisoryx_refsource_FEDORA
https://lists.fedoraproject.org/archives/list/pac…	vendor-advisoryx_refsource_FEDORA
https://security.gentoo.org/glsa/202105-11	vendor-advisoryx_refsource_GENTOO
https://security.netapp.com/advisory/ntap-2025050…

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.

Vulnerability timeline

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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.

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