Vulnerability-Lookup

MSRC_CVE-2026-5187

Vulnerability from csaf_microsoft - Published: 2026-04-02 00:00 - Updated: 2026-04-24 01:39

Summary

Heap Out-of-Bounds Write in DecodeObjectId() in wolfSSL

Notes

Additional Resources: To determine the support lifecycle for your software, see the Microsoft Support Lifecycle: https://support.microsoft.com/lifecycle

Disclaimer: The information provided in the Microsoft Knowledge Base is provided \"as is\" without warranty of any kind. Microsoft disclaims all warranties, either express or implied, including the warranties of merchantability and fitness for a particular purpose. In no event shall Microsoft Corporation or its suppliers be liable for any damages whatsoever including direct, indirect, incidental, consequential, loss of business profits or special damages, even if Microsoft Corporation or its suppliers have been advised of the possibility of such damages. Some states do not allow the exclusion or limitation of liability for consequential or incidental damages so the foregoing limitation may not apply.

CVE-2026-5187

CWE-122 - Heap-based Buffer Overflow

None Available There is no fix available for this vulnerability as of now

References

URL

Category

	https://msrc.microsoft.com/csaf/vex/2026/msrc_cve…	self
	https://support.microsoft.com/lifecycle	external
	https://www.first.org/cvss	external
	https://msrc.microsoft.com/csaf/vex/2026/msrc_cve…	self

JSON

To clipboard

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      "tlp": {
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        "title": "Additional Resources"
      },
      {
        "category": "legal_disclaimer",
        "text": "The information provided in the Microsoft Knowledge Base is provided \\\"as is\\\" without warranty of any kind. Microsoft disclaims all warranties, either express or implied, including the warranties of merchantability and fitness for a particular purpose. In no event shall Microsoft Corporation or its suppliers be liable for any damages whatsoever including direct, indirect, incidental, consequential, loss of business profits or special damages, even if Microsoft Corporation or its suppliers have been advised of the possibility of such damages. Some states do not allow the exclusion or limitation of liability for consequential or incidental damages so the foregoing limitation may not apply.",
        "title": "Disclaimer"
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        "summary": "Common Vulnerability Scoring System",
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    ],
    "title": "Heap Out-of-Bounds Write in DecodeObjectId() in wolfSSL",
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  "vulnerabilities": [
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      "cwe": {
        "id": "CWE-122",
        "name": "Heap-based Buffer Overflow"
      },
      "notes": [
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      ],
      "title": "Heap Out-of-Bounds Write in DecodeObjectId() in wolfSSL"
    }
  ]
}

CVE-2026-5187 (GCVE-0-2026-5187)

Vulnerability from cvelistv5 – Published: 2026-04-09 19:45 – Updated: 2026-04-14 14:04

Title

Heap Out-of-Bounds Write in DecodeObjectId() in wolfSSL

Summary

Two potential heap out-of-bounds write locations existed in DecodeObjectId() in wolfcrypt/src/asn.c. First, a bounds check only validates one available slot before writing two OID arc values (out[0] and out[1]), enabling a 2-byte out-of-bounds write when outSz equals 1. Second, multiple callers pass sizeof(decOid) (64 bytes on 64-bit platforms) instead of the element count MAX_OID_SZ (32), causing the function to accept crafted OIDs with 33 or more arcs that write past the end of the allocated buffer.

Severity ?

2.3 (Low)


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

CWE

CWE-122 - Heap-based Buffer Overflow
CWE-787 - Out-of-bounds Write

Assigner

wolfSSL

References

URL

Tags

https://github.com/wolfSSL/wolfssl

Impacted products

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

Credits

ytsun, Independent Security Researcher

Show details on NVD website

JSON

To clipboard

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Sightings

Author	Source	Type	Date

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.

Action not permitted

MSRC_CVE-2026-5187

CVE-2026-5187 (GCVE-0-2026-5187)

Tags

Sightings

Nomenclature