Vulnerability-Lookup

CNVD-2026-21721

Vulnerability from cnvd - Published: 2026-05-27

Title

wolfSSL堆溢出漏洞

Description

wolfSSL（CyaSSL）是美国wolfSSL公司的一个针对嵌入式系统开发人员使用的小的、可移植的嵌入式SSL编程库。 wolfSSL存在堆溢出漏洞，攻击者可利用该漏洞导致写入超出已分配缓冲区的边界。

Severity

高

Patch Name

wolfSSL堆溢出漏洞的补丁

Patch Description

wolfSSL（CyaSSL）是美国wolfSSL公司的一个针对嵌入式系统开发人员使用的小的、可移植的嵌入式SSL编程库。 wolfSSL存在堆溢出漏洞，攻击者可利用该漏洞导致写入超出已分配缓冲区的边界。目前，供应商发布了安全公告及相关补丁信息，修复了此漏洞。

Formal description

厂商已发布了漏洞修复程序，请及时关注更新： https://github.com/wolfSSL/wolfssl/releases

Reference

https://github.com/wolfSSL/wolfssl/pull/9817

Impacted products

Name
wolfSSL WolfSSL <5.9.0

Show details on source website

JSON

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{
  "cves": {
    "cve": {
      "cveNumber": "CVE-2026-3549",
      "cveUrl": "https://nvd.nist.gov/vuln/detail/CVE-2026-3549"
    }
  },
  "description": "wolfSSL\uff08CyaSSL\uff09\u662f\u7f8e\u56fdwolfSSL\u516c\u53f8\u7684\u4e00\u4e2a\u9488\u5bf9\u5d4c\u5165\u5f0f\u7cfb\u7edf\u5f00\u53d1\u4eba\u5458\u4f7f\u7528\u7684\u5c0f\u7684\u3001\u53ef\u79fb\u690d\u7684\u5d4c\u5165\u5f0fSSL\u7f16\u7a0b\u5e93\u3002\n\nwolfSSL\u5b58\u5728\u5806\u6ea2\u51fa\u6f0f\u6d1e\uff0c\u653b\u51fb\u8005\u53ef\u5229\u7528\u8be5\u6f0f\u6d1e\u5bfc\u81f4\u5199\u5165\u8d85\u51fa\u5df2\u5206\u914d\u7f13\u51b2\u533a\u7684\u8fb9\u754c\u3002",
  "formalWay": "\u5382\u5546\u5df2\u53d1\u5e03\u4e86\u6f0f\u6d1e\u4fee\u590d\u7a0b\u5e8f\uff0c\u8bf7\u53ca\u65f6\u5173\u6ce8\u66f4\u65b0\uff1a\r\nhttps://github.com/wolfSSL/wolfssl/releases",
  "isEvent": "\u901a\u7528\u8f6f\u786c\u4ef6\u6f0f\u6d1e",
  "number": "CNVD-2026-21721",
  "openTime": "2026-05-27",
  "patchDescription": "wolfSSL\uff08CyaSSL\uff09\u662f\u7f8e\u56fdwolfSSL\u516c\u53f8\u7684\u4e00\u4e2a\u9488\u5bf9\u5d4c\u5165\u5f0f\u7cfb\u7edf\u5f00\u53d1\u4eba\u5458\u4f7f\u7528\u7684\u5c0f\u7684\u3001\u53ef\u79fb\u690d\u7684\u5d4c\u5165\u5f0fSSL\u7f16\u7a0b\u5e93\u3002\r\n\r\nwolfSSL\u5b58\u5728\u5806\u6ea2\u51fa\u6f0f\u6d1e\uff0c\u653b\u51fb\u8005\u53ef\u5229\u7528\u8be5\u6f0f\u6d1e\u5bfc\u81f4\u5199\u5165\u8d85\u51fa\u5df2\u5206\u914d\u7f13\u51b2\u533a\u7684\u8fb9\u754c\u3002\u76ee\u524d\uff0c\u4f9b\u5e94\u5546\u53d1\u5e03\u4e86\u5b89\u5168\u516c\u544a\u53ca\u76f8\u5173\u8865\u4e01\u4fe1\u606f\uff0c\u4fee\u590d\u4e86\u6b64\u6f0f\u6d1e\u3002",
  "patchName": "wolfSSL\u5806\u6ea2\u51fa\u6f0f\u6d1e\u7684\u8865\u4e01",
  "products": {
    "product": "wolfSSL WolfSSL \u003c5.9.0"
  },
  "referenceLink": "https://github.com/wolfSSL/wolfssl/pull/9817",
  "serverity": "\u9ad8",
  "submitTime": "2026-03-26",
  "title": "wolfSSL\u5806\u6ea2\u51fa\u6f0f\u6d1e"
}

CVE-2026-3549 (GCVE-0-2026-3549)

Vulnerability from cvelistv5 – Published: 2026-03-19 20:09 – Updated: 2026-03-24 01:38

Title

ECH parsing heap buffer overflow

Summary

Heap Overflow in TLS 1.3 ECH parsing. An integer underflow existed in ECH extension parsing logic when calculating a buffer length, which resulted in writing beyond the bounds of an allocated buffer. Note that in wolfSSL, ECH is off by default, and the ECH standard is still evolving.

Severity

8.3 (High)


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

SSVC

Exploitation: none Automatable: yes Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-03-24 01:37 UTC

CWE

CWE-122 - Heap-based buffer overflow

Assigner

wolfSSL icscert root

References

1 reference

URL	Tags
https://github.com/wolfSSL/wolfssl/pull/9817

Impacted products

1 product

Vendor	Product	Version
wofSSL	wolfSSL	Affected: 0 , < 5.9.0 (semver)

Credits

Oleh Konko for independently reporting after internal wolfSSL findings and testing wolfSSL's fix

Show details on NVD website

JSON

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                "role": "CISA Coordinator",
                "timestamp": "2026-03-24T01:37:47.102762Z",
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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.

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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.