Vulnerability-Lookup

GHSA-3CR6-HPF3-2HMG

Vulnerability from github – Published: 2026-03-19 18:31 – Updated: 2026-03-19 18:31

Details

A stack buffer overflow vulnerability exists in wolfSSL's PKCS7 SignedData encoding functionality. In wc_PKCS7_BuildSignedAttributes(), when adding custom signed attributes, the code passes an incorrect capacity value (esd->signedAttribsCount) to EncodeAttributes() instead of the remaining available space in the fixed-size signedAttribs[7] array. When an application sets pkcs7->signedAttribsSz to a value greater than MAX_SIGNED_ATTRIBS_SZ (default 7) minus the number of default attributes already added, EncodeAttributes() writes beyond the array bounds, causing stack memory corruption. In WOLFSSL_SMALL_STACK builds, this becomes heap corruption. Exploitation requires an application that allows untrusted input to control the signedAttribs array size when calling wc_PKCS7_EncodeSignedData() or related signing functions.

Severity ?

2.2 (Low)


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

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{
  "affected": [],
  "aliases": [
    "CVE-2026-0819"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-121"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-03-19T17:16:21Z",
    "severity": "LOW"
  },
  "details": "A stack buffer overflow vulnerability exists in wolfSSL\u0027s PKCS7 SignedData encoding functionality. In wc_PKCS7_BuildSignedAttributes(), when adding custom signed attributes, the code passes an incorrect capacity value (esd-\u003esignedAttribsCount) to EncodeAttributes() instead of the remaining available space in the fixed-size signedAttribs[7] array. When an application sets pkcs7-\u003esignedAttribsSz to a value greater than MAX_SIGNED_ATTRIBS_SZ (default 7) minus the number of default attributes already added, EncodeAttributes() writes beyond the array bounds, causing stack memory corruption. In WOLFSSL_SMALL_STACK builds, this becomes heap corruption. Exploitation requires an application that allows untrusted input to control the signedAttribs array size when calling wc_PKCS7_EncodeSignedData() or related signing functions.",
  "id": "GHSA-3cr6-hpf3-2hmg",
  "modified": "2026-03-19T18:31:18Z",
  "published": "2026-03-19T18:31:18Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-0819"
    },
    {
      "type": "WEB",
      "url": "https://github.com/wolfSSL/wolfssl/pull/9630"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
      "type": "CVSS_V4"
    }
  ]
}

CVE-2026-0819 (GCVE-0-2026-0819)

Vulnerability from cvelistv5 – Published: 2026-03-19 16:54 – Updated: 2026-03-19 17:19

Title

Stack buffer overflow in PKCS7 SignedData encoding with custom signed attributes

Summary

Severity ?

2.2 (Low)


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

CWE

CWE-121 - Stack-based Buffer Overflow
CWE-787 - Out-of-bounds Write

Assigner

wolfSSL

References

URL

Tags

https://github.com/wolfSSL/wolfssl/pull/9630

Impacted products

	Vendor	Product	Version
	wolfSSL	wolfSSL	Affected: 5.5.0 , < 5.9.0 (semver)

Credits

Maor Caplan

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JSON

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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

GHSA-3CR6-HPF3-2HMG

CVE-2026-0819 (GCVE-0-2026-0819)

Tags

Sightings

Nomenclature