Staging Environment: Content and features may be unstable or change without notice.
Search for vulnerabilities
Vulnerability details: VCID-1mkj-94qc-zqgn
Vulnerability ID VCID-1mkj-94qc-zqgn
Aliases CVE-2021-3711
GHSA-5ww6-px42-wc85
Summary Buffer Overflow In order to decrypt SM2 encrypted data an application is expected to call the API function `EVP_PKEY_decrypt()`. Typically an application will call this function twice. The first time, on entry, the `out` parameter can be NULL and, on exit, the `outlen` parameter is populated with the buffer size required to hold the decrypted plaintext. The application can then allocate a sufficiently sized buffer and call `EVP_PKEY_decrypt()` again, but this time passing a non-NULL value for the `out` parameter. A bug in the implementation of the SM2 decryption code means that the calculation of the buffer size required to hold the plaintext returned by the first call to `EVP_PKEY_decrypt()` can be smaller than the actual size required by the second call. This can lead to a buffer overflow when `EVP_PKEY_decrypt()` is called by the application a second time with a buffer that is too small. A malicious attacker who is able present SM2 content for decryption to an application could cause attacker chosen data to overflow the buffer by up to a maximum of bytes altering the contents of other data held after the buffer, possibly changing application behaviour or causing the application to crash. The location of the buffer is application dependent but is typically heap allocated.
Status Published
Exploitability 0.5
Weighted Severity 9.0
Risk 4.5
Affected and Fixed Packages Package Details
Weaknesses (4)
CWE-1035 OWASP Top Ten 2017 Category A9 - Using Components with Known Vulnerabilities
CWE-120 Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')
CWE-937 OWASP Top Ten 2013 Category A9 - Using Components with Known Vulnerabilities
CWE-787 Out-of-bounds Write
System Score Found at
cvssv3 9.8 https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2021-3711.json
epss 0.02293 https://api.first.org/data/v1/epss?cve=CVE-2021-3711
epss 0.02293 https://api.first.org/data/v1/epss?cve=CVE-2021-3711
epss 0.02293 https://api.first.org/data/v1/epss?cve=CVE-2021-3711
epss 0.02293 https://api.first.org/data/v1/epss?cve=CVE-2021-3711
epss 0.02293 https://api.first.org/data/v1/epss?cve=CVE-2021-3711
epss 0.02544 https://api.first.org/data/v1/epss?cve=CVE-2021-3711
epss 0.02544 https://api.first.org/data/v1/epss?cve=CVE-2021-3711
epss 0.02544 https://api.first.org/data/v1/epss?cve=CVE-2021-3711
epss 0.02544 https://api.first.org/data/v1/epss?cve=CVE-2021-3711
cvssv3.1 9.8 https://cert-portal.siemens.com/productcert/pdf/ssa-389290.pdf
generic_textual CRITICAL https://cert-portal.siemens.com/productcert/pdf/ssa-389290.pdf
cvssv3.1 9.8 https://ftp.suse.com/pub/projects/security/yaml/suse-cvss-scores.yaml
cvssv3.1_qr CRITICAL https://github.com/advisories/GHSA-5ww6-px42-wc85
cvssv3.1 9.8 https://git.openssl.org/gitweb/?p=openssl.git%3Ba=commitdiff%3Bh=59f5e75f3bced8fc0e130d72a3f582cf7b480b46
generic_textual CRITICAL https://git.openssl.org/gitweb/?p=openssl.git%3Ba=commitdiff%3Bh=59f5e75f3bced8fc0e130d72a3f582cf7b480b46
cvssv3.1 9.8 https://git.openssl.org/gitweb/?p=openssl.git;a=commitdiff;h=59f5e75f3bced8fc0e130d72a3f582cf7b480b46
generic_textual CRITICAL https://git.openssl.org/gitweb/?p=openssl.git;a=commitdiff;h=59f5e75f3bced8fc0e130d72a3f582cf7b480b46
cvssv3.1 9.8 https://lists.apache.org/thread.html/r18995de860f0e63635f3008fd2a6aca82394249476d21691e7c59c9e@%3Cdev.tomcat.apache.org%3E
generic_textual CRITICAL https://lists.apache.org/thread.html/r18995de860f0e63635f3008fd2a6aca82394249476d21691e7c59c9e@%3Cdev.tomcat.apache.org%3E
cvssv3.1 9.8 https://lists.apache.org/thread.html/r18995de860f0e63635f3008fd2a6aca82394249476d21691e7c59c9e%40%3Cdev.tomcat.apache.org%3E
generic_textual CRITICAL https://lists.apache.org/thread.html/r18995de860f0e63635f3008fd2a6aca82394249476d21691e7c59c9e%40%3Cdev.tomcat.apache.org%3E
cvssv3.1 9.8 https://lists.apache.org/thread.html/rad5d9f83f0d11fb3f8bb148d179b8a9ad7c6a17f18d70e5805a713d1@%3Cdev.tomcat.apache.org%3E
generic_textual CRITICAL https://lists.apache.org/thread.html/rad5d9f83f0d11fb3f8bb148d179b8a9ad7c6a17f18d70e5805a713d1@%3Cdev.tomcat.apache.org%3E
cvssv3.1 9.8 https://lists.apache.org/thread.html/rad5d9f83f0d11fb3f8bb148d179b8a9ad7c6a17f18d70e5805a713d1%40%3Cdev.tomcat.apache.org%3E
generic_textual CRITICAL https://lists.apache.org/thread.html/rad5d9f83f0d11fb3f8bb148d179b8a9ad7c6a17f18d70e5805a713d1%40%3Cdev.tomcat.apache.org%3E
cvssv3.1 9.8 https://nvd.nist.gov/vuln/detail/CVE-2021-3711
generic_textual CRITICAL https://nvd.nist.gov/vuln/detail/CVE-2021-3711
cvssv3.1 9.8 https://rustsec.org/advisories/RUSTSEC-2021-0097.html
generic_textual CRITICAL https://rustsec.org/advisories/RUSTSEC-2021-0097.html
archlinux High https://security.archlinux.org/AVG-2315
archlinux High https://security.archlinux.org/AVG-2316
cvssv3.1 9.8 https://security.gentoo.org/glsa/202209-02
generic_textual CRITICAL https://security.gentoo.org/glsa/202209-02
cvssv3.1 9.8 https://security.gentoo.org/glsa/202210-02
generic_textual CRITICAL https://security.gentoo.org/glsa/202210-02
cvssv3.1 9.8 https://security.netapp.com/advisory/ntap-20210827-0010
generic_textual CRITICAL https://security.netapp.com/advisory/ntap-20210827-0010
cvssv3.1 9.8 https://security.netapp.com/advisory/ntap-20211022-0003
generic_textual CRITICAL https://security.netapp.com/advisory/ntap-20211022-0003
cvssv3.1 9.8 https://security.netapp.com/advisory/ntap-20240621-0006
generic_textual CRITICAL https://security.netapp.com/advisory/ntap-20240621-0006
cvssv3.1 9.8 https://www.debian.org/security/2021/dsa-4963
generic_textual CRITICAL https://www.debian.org/security/2021/dsa-4963
cvssv3.1 9.8 https://www.openssl.org/news/secadv/20210824.txt
generic_textual CRITICAL https://www.openssl.org/news/secadv/20210824.txt
cvssv3.1 9.8 https://www.oracle.com/security-alerts/cpuapr2022.html
generic_textual CRITICAL https://www.oracle.com/security-alerts/cpuapr2022.html
cvssv3.1 9.8 https://www.oracle.com/security-alerts/cpujan2022.html
generic_textual CRITICAL https://www.oracle.com/security-alerts/cpujan2022.html
cvssv3.1 9.8 https://www.oracle.com/security-alerts/cpuoct2021.html
generic_textual CRITICAL https://www.oracle.com/security-alerts/cpuoct2021.html
cvssv3.1 9.8 https://www.tenable.com/security/tns-2021-16
generic_textual CRITICAL https://www.tenable.com/security/tns-2021-16
cvssv3.1 9.8 https://www.tenable.com/security/tns-2022-02
generic_textual CRITICAL https://www.tenable.com/security/tns-2022-02
cvssv3.1 9.8 http://www.openwall.com/lists/oss-security/2021/08/26/2
generic_textual CRITICAL http://www.openwall.com/lists/oss-security/2021/08/26/2
Reference id Reference type URL
https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2021-3711.json
https://api.first.org/data/v1/epss?cve=CVE-2021-3711
https://cert-portal.siemens.com/productcert/pdf/ssa-389290.pdf
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-3711
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-3712
https://ftp.suse.com/pub/projects/security/yaml/suse-cvss-scores.yaml
https://git.openssl.org/gitweb/?p=openssl.git%3Ba=commitdiff%3Bh=59f5e75f3bced8fc0e130d72a3f582cf7b480b46
https://git.openssl.org/gitweb/?p=openssl.git;a=commitdiff;h=59f5e75f3bced8fc0e130d72a3f582cf7b480b46
https://lists.apache.org/thread.html/r18995de860f0e63635f3008fd2a6aca82394249476d21691e7c59c9e@%3Cdev.tomcat.apache.org%3E
https://lists.apache.org/thread.html/r18995de860f0e63635f3008fd2a6aca82394249476d21691e7c59c9e%40%3Cdev.tomcat.apache.org%3E
https://lists.apache.org/thread.html/rad5d9f83f0d11fb3f8bb148d179b8a9ad7c6a17f18d70e5805a713d1@%3Cdev.tomcat.apache.org%3E
https://lists.apache.org/thread.html/rad5d9f83f0d11fb3f8bb148d179b8a9ad7c6a17f18d70e5805a713d1%40%3Cdev.tomcat.apache.org%3E
https://rustsec.org/advisories/RUSTSEC-2021-0097.html
https://security.gentoo.org/glsa/202209-02
https://security.netapp.com/advisory/ntap-20210827-0010
https://security.netapp.com/advisory/ntap-20211022-0003
https://security.netapp.com/advisory/ntap-20240621-0006
https://www.debian.org/security/2021/dsa-4963
https://www.openssl.org/news/secadv/20210824.txt
https://www.oracle.com/security-alerts/cpuapr2022.html
https://www.oracle.com/security-alerts/cpujan2022.html
https://www.oracle.com/security-alerts/cpuoct2021.html
https://www.tenable.com/security/tns-2021-16
https://www.tenable.com/security/tns-2022-02
http://www.openwall.com/lists/oss-security/2021/08/26/2
1995623 https://bugzilla.redhat.com/show_bug.cgi?id=1995623
AVG-2315 https://security.archlinux.org/AVG-2315
AVG-2316 https://security.archlinux.org/AVG-2316
CVE-2021-3711 https://nvd.nist.gov/vuln/detail/CVE-2021-3711
GHSA-5ww6-px42-wc85 https://github.com/advisories/GHSA-5ww6-px42-wc85
GLSA-202210-02 https://security.gentoo.org/glsa/202210-02
USN-5051-1 https://usn.ubuntu.com/5051-1/
No exploits are available.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Found at https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2021-3711.json
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Found at https://cert-portal.siemens.com/productcert/pdf/ssa-389290.pdf
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Found at https://ftp.suse.com/pub/projects/security/yaml/suse-cvss-scores.yaml
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Found at https://git.openssl.org/gitweb/?p=openssl.git%3Ba=commitdiff%3Bh=59f5e75f3bced8fc0e130d72a3f582cf7b480b46
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Found at https://git.openssl.org/gitweb/?p=openssl.git;a=commitdiff;h=59f5e75f3bced8fc0e130d72a3f582cf7b480b46
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Found at https://lists.apache.org/thread.html/r18995de860f0e63635f3008fd2a6aca82394249476d21691e7c59c9e@%3Cdev.tomcat.apache.org%3E
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Found at https://lists.apache.org/thread.html/r18995de860f0e63635f3008fd2a6aca82394249476d21691e7c59c9e%40%3Cdev.tomcat.apache.org%3E
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Found at https://lists.apache.org/thread.html/rad5d9f83f0d11fb3f8bb148d179b8a9ad7c6a17f18d70e5805a713d1@%3Cdev.tomcat.apache.org%3E
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Found at https://lists.apache.org/thread.html/rad5d9f83f0d11fb3f8bb148d179b8a9ad7c6a17f18d70e5805a713d1%40%3Cdev.tomcat.apache.org%3E
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Found at https://nvd.nist.gov/vuln/detail/CVE-2021-3711
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Found at https://rustsec.org/advisories/RUSTSEC-2021-0097.html
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Found at https://security.gentoo.org/glsa/202209-02
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Found at https://security.gentoo.org/glsa/202210-02
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Found at https://security.netapp.com/advisory/ntap-20210827-0010
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Found at https://security.netapp.com/advisory/ntap-20211022-0003
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Found at https://security.netapp.com/advisory/ntap-20240621-0006
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Found at https://www.debian.org/security/2021/dsa-4963
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Found at https://www.openssl.org/news/secadv/20210824.txt
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Found at https://www.oracle.com/security-alerts/cpuapr2022.html
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Found at https://www.oracle.com/security-alerts/cpujan2022.html
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Found at https://www.oracle.com/security-alerts/cpuoct2021.html
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Found at https://www.tenable.com/security/tns-2021-16
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Found at https://www.tenable.com/security/tns-2022-02
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Found at http://www.openwall.com/lists/oss-security/2021/08/26/2
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Exploit Prediction Scoring System (EPSS)
Percentile 0.84644
EPSS Score 0.02293
Published At April 1, 2026, 12:55 p.m.
Date Actor Action Source VulnerableCode Version
2026-04-01T12:48:41.056012+00:00 GitLab Importer Import https://gitlab.com/gitlab-org/advisories-community/-/blob/main/conan/openssl/CVE-2021-3711.yml 38.0.0