CVE-2026-7383

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Source
https://cve.org/CVERecord?id=CVE-2026-7383
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-7383.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-7383
Downstream
Related
Published
2026-06-09T16:03:15.508Z
Modified
2026-07-22T00:45:50.255524Z
Severity
  • 8.1 (High) CVSS_V3 - CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H CVSS Calculator
Summary
Possible Heap Buffer Overflow in ASN.1 Multibyte String Conversion
Details

Issue summary: A signed integer overflow when sizing the destination buffer for Unicode output in ASN1mbstringncopy() can lead to a heap buffer overflow.

Impact summary: A heap buffer overflow may lead to a crash or possibly attacker controlled code execution or other undefined behaviour.

In ASN1mbstringcopy() and ASN1mbstringncopy() the destination size for Unicode output is computed in a signed int: by left shift of the input character count for BMPSTRING (UTF-16) and UNIVERSALSTRING (UTF-32), and by summing per-character byte counts for UTF8STRING. The calculation overflows when the input reaches around 2^30 characters. In the worst case (UNIVERSALSTRING at 2^30 characters) the size wraps to zero, OPENSSL_malloc(1) is called, and the subsequent character copy writes several gigabytes past the one-byte allocation.

X.509 certificate processing routes through ASN1STRINGsetbyNID(), whose DIRSTRINGTYPE mask excludes UNIVERSALSTRING and whose per-NID size limits cap the input length; no network protocol or certificate-handling path in OpenSSL exercises the overflow. Triggering the bug requires an application that calls ASN1mbstringcopy() or ASN1mbstringncopy() directly, or registers a custom string type via ASN1STRINGTABLEadd(), with attacker-controlled input on the order of half a gigabyte or more. For these reasons this issue was assigned Low severity.

The FIPS modules in 4.0, 3.6, 3.5, 3.4 and 3.0 are not affected by this issue, as the affected code is outside the OpenSSL FIPS module boundary.

Database specific 
{
    "cwe_ids": [
        "CWE-787"
    ],
    "cna_assigner": "openssl",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/7xxx/CVE-2026-7383.json"
}
References

Affected packages

Git / github.com/openssl/openssl

Affected ranges

Type
GIT
Repo
https://github.com/openssl/openssl
Events
Introduced
e818b74be2170fbe957a07b0da4401c2b694b3b8
Fixed
e818b74be2170fbe957a07b0da4401c2b694b3b8
Introduced
e04bd3433fd84e1861bf258ea37928d9845e6a86
Fixed
e04bd3433fd84e1861bf258ea37928d9845e6a86
Introduced
89cd17a031e022211684eb7eb41190cf1910f9fa
Fixed
51ea949dc1436e865935b47874b21a3bb31a102e
Introduced
98acb6b02839c609ef5b837794e08d906d965335
Fixed
c5ea1cc227fd60afae8ac4b9438690bbe4888f79
Introduced
636dfadc70ce26f2473870570bfd9ec352806b1d
Fixed
8cf17aaeb4599f8af87fefd810b5b5fee90fe69e
Introduced
7b371d80d959ec9ab4139d09d78e83c090de9779
Fixed
aae016bfd52fcad2bc9657c2c782cfdf73b1ed5f
Introduced
11b7b6ea3b65a584e1d31408ed1bdb139465cffd
Fixed
4f8d2bddaa2c8e06f9c33390ee1717059a6e4be6
Fixed
80c15faaf78042bbb8654a0e234c50c381732f74
Fixed
bd17511070fb39a67bfa19682affb765e706a974
Fixed
c332adaced43bcbb85f97410597e951c11ec3083
Fixed
d32350ae8ef7426718f5aa9e383d4b51398ee255
Database specific 
{
    "cpe": [
        "cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:*",
        "cpe:2.3:a:openssl:openssl:4.0.0:-:*:*:*:*:*:*"
    ],
    "extracted_events": [
        {
            "introduced": "1.0.2"
        },
        {
            "fixed": "1.0.2zq"
        },
        {
            "introduced": "1.1.1"
        },
        {
            "fixed": "1.1.1zh"
        },
        {
            "introduced": "3.0.0"
        },
        {
            "fixed": "3.0.21"
        },
        {
            "introduced": "3.4.0"
        },
        {
            "fixed": "3.4.6"
        },
        {
            "introduced": "3.5.0"
        },
        {
            "fixed": "3.5.7"
        },
        {
            "introduced": "3.6.0"
        },
        {
            "fixed": "3.6.3"
        },
        {
            "introduced": "4.0.0-NA"
        },
        {
            "last_affected": "4.0.0-NA"
        }
    ],
    "source": [
        "CPE_RANGE",
        "CPE_STRING",
        "REFERENCES"
    ]
}

Affected versions

3.*
3.0-POST-CLANG-FORMAT-WEBKIT
3.0-PRE-CLANG-FORMAT-WEBKIT
3.4-POST-CLANG-FORMAT-WEBKIT
3.4-PRE-CLANG-FORMAT-WEBKIT
3.5-POST-CLANG-FORMAT-WEBKIT
3.5-PRE-CLANG-FORMAT-WEBKIT
3.6-POST-CLANG-FORMAT-WEBKIT
3.6-PRE-CLANG-FORMAT-WEBKIT
4.*
4.0.0-NA
openssl-3.*
openssl-3.0.0
openssl-3.0.1
openssl-3.0.10
openssl-3.0.11
openssl-3.0.12
openssl-3.0.13
openssl-3.0.14
openssl-3.0.15
openssl-3.0.16
openssl-3.0.17
openssl-3.0.18
openssl-3.0.19
openssl-3.0.2
openssl-3.0.20
openssl-3.0.3
openssl-3.0.4
openssl-3.0.5
openssl-3.0.6
openssl-3.0.7
openssl-3.0.8
openssl-3.0.9
openssl-3.4.0
openssl-3.4.1
openssl-3.4.2
openssl-3.4.3
openssl-3.4.4
openssl-3.4.5
openssl-3.5.0
openssl-3.5.1
openssl-3.5.2
openssl-3.5.3
openssl-3.5.4
openssl-3.5.5
openssl-3.5.6
openssl-3.6.0
openssl-3.6.1
openssl-3.6.2
openssl-4.*
openssl-4.0.0

Database specific

vanir_signatures_modified 
"2026-07-22T00:45:50Z"
vanir_signatures 
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        "deprecated": false,
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            "threshold": 0.9,
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        },
        "signature_version": "v1",
        "source": "https://github.com/openssl/openssl/commit/4f8d2bddaa2c8e06f9c33390ee1717059a6e4be6",
        "id": "CVE-2026-7383-03cd20c7",
        "target": {
            "file": "crypto/asn1/a_mbstr.c"
        }
    },
    {
        "signature_type": "Function",
        "deprecated": false,
        "digest": {
            "length": 3297.0,
            "function_hash": "157368430457296408057518218641344868108"
        },
        "signature_version": "v1",
        "source": "https://github.com/openssl/openssl/commit/d32350ae8ef7426718f5aa9e383d4b51398ee255",
        "id": "CVE-2026-7383-1be3bd59",
        "target": {
            "function": "ASN1_mbstring_ncopy",
            "file": "crypto/asn1/a_mbstr.c"
        }
    },
    {
        "signature_type": "Function",
        "deprecated": false,
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        },
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        "id": "CVE-2026-7383-35f12443",
        "target": {
            "function": "out_utf8",
            "file": "crypto/asn1/a_mbstr.c"
        }
    },
    {
        "signature_type": "Line",
        "deprecated": false,
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        },
        "signature_version": "v1",
        "source": "https://github.com/openssl/openssl/commit/d32350ae8ef7426718f5aa9e383d4b51398ee255",
        "id": "CVE-2026-7383-53da0590",
        "target": {
            "file": "crypto/asn1/a_mbstr.c"
        }
    },
    {
        "signature_type": "Function",
        "deprecated": false,
        "digest": {
            "length": 195.0,
            "function_hash": "326715636192485159031379249291784863467"
        },
        "signature_version": "v1",
        "source": "https://github.com/openssl/openssl/commit/c332adaced43bcbb85f97410597e951c11ec3083",
        "id": "CVE-2026-7383-5a2e414f",
        "target": {
            "function": "out_utf8",
            "file": "crypto/asn1/a_mbstr.c"
        }
    },
    {
        "signature_type": "Line",
        "deprecated": false,
        "digest": {
            "threshold": 0.9,
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        },
        "signature_version": "v1",
        "source": "https://github.com/openssl/openssl/commit/bd17511070fb39a67bfa19682affb765e706a974",
        "id": "CVE-2026-7383-6d93e3cf",
        "target": {
            "file": "crypto/asn1/a_mbstr.c"
        }
    },
    {
        "signature_type": "Function",
        "deprecated": false,
        "digest": {
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            "function_hash": "186349096673253037366471905327905215678"
        },
        "signature_version": "v1",
        "source": "https://github.com/openssl/openssl/commit/bd17511070fb39a67bfa19682affb765e706a974",
        "id": "CVE-2026-7383-6ea28808",
        "target": {
            "function": "ASN1_mbstring_ncopy",
            "file": "crypto/asn1/a_mbstr.c"
        }
    },
    {
        "signature_type": "Function",
        "deprecated": false,
        "digest": {
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            "function_hash": "326715636192485159031379249291784863467"
        },
        "signature_version": "v1",
        "source": "https://github.com/openssl/openssl/commit/4f8d2bddaa2c8e06f9c33390ee1717059a6e4be6",
        "id": "CVE-2026-7383-6ecfcbdc",
        "target": {
            "function": "out_utf8",
            "file": "crypto/asn1/a_mbstr.c"
        }
    },
    {
        "signature_type": "Line",
        "deprecated": false,
        "digest": {
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        "source": "https://github.com/openssl/openssl/commit/80c15faaf78042bbb8654a0e234c50c381732f74",
        "id": "CVE-2026-7383-7397b06f",
        "target": {
            "file": "crypto/asn1/a_mbstr.c"
        }
    },
    {
        "signature_type": "Function",
        "deprecated": false,
        "digest": {
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            "function_hash": "65331361705884786675178309567558276074"
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        "id": "CVE-2026-7383-810515e4",
        "target": {
            "function": "ASN1_mbstring_ncopy",
            "file": "crypto/asn1/a_mbstr.c"
        }
    },
    {
        "signature_type": "Function",
        "deprecated": false,
        "digest": {
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            "function_hash": "65331361705884786675178309567558276074"
        },
        "signature_version": "v1",
        "source": "https://github.com/openssl/openssl/commit/80c15faaf78042bbb8654a0e234c50c381732f74",
        "id": "CVE-2026-7383-81b05481",
        "target": {
            "function": "ASN1_mbstring_ncopy",
            "file": "crypto/asn1/a_mbstr.c"
        }
    },
    {
        "signature_type": "Function",
        "deprecated": false,
        "digest": {
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        },
        "signature_version": "v1",
        "source": "https://github.com/openssl/openssl/commit/80c15faaf78042bbb8654a0e234c50c381732f74",
        "id": "CVE-2026-7383-a18e4192",
        "target": {
            "function": "out_utf8",
            "file": "crypto/asn1/a_mbstr.c"
        }
    },
    {
        "signature_type": "Line",
        "deprecated": false,
        "digest": {
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        "target": {
            "file": "include/openssl/opensslv.h"
        }
    },
    {
        "signature_type": "Line",
        "deprecated": false,
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        "target": {
            "file": "crypto/asn1/a_mbstr.c"
        }
    },
    {
        "signature_type": "Line",
        "deprecated": false,
        "digest": {
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        "signature_version": "v1",
        "source": "https://github.com/openssl/openssl/commit/e818b74be2170fbe957a07b0da4401c2b694b3b8",
        "id": "CVE-2026-7383-e051451f",
        "target": {
            "file": "crypto/opensslv.h"
        }
    },
    {
        "signature_type": "Function",
        "deprecated": false,
        "digest": {
            "length": 3297.0,
            "function_hash": "157368430457296408057518218641344868108"
        },
        "signature_version": "v1",
        "source": "https://github.com/openssl/openssl/commit/c332adaced43bcbb85f97410597e951c11ec3083",
        "id": "CVE-2026-7383-e999ea89",
        "target": {
            "function": "ASN1_mbstring_ncopy",
            "file": "crypto/asn1/a_mbstr.c"
        }
    },
    {
        "signature_type": "Function",
        "deprecated": false,
        "digest": {
            "length": 195.0,
            "function_hash": "326715636192485159031379249291784863467"
        },
        "signature_version": "v1",
        "source": "https://github.com/openssl/openssl/commit/bd17511070fb39a67bfa19682affb765e706a974",
        "id": "CVE-2026-7383-fb21566a",
        "target": {
            "function": "out_utf8",
            "file": "crypto/asn1/a_mbstr.c"
        }
    }
]
source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-7383.json"