CVE-2021-3711
CriticalSM2 Decryption Buffer Overflow
Published Mar 11, 2022 · Updated Oct 10, 2026 · Also known as ALPINE-CVE-2021-3711, DEBIAN-CVE-2021-3711, DSA-4963-1, EUVD-2022-2673, GHSA-5ww6-px42-wc85, JLSEC-2026-224, RUSTSEC-2021-0097, SUSE-SU-2021:2830-1, SUSE-SU-2021:2833-1, UBUNTU-CVE-2021-3711, USN-5051-1
Key Facts
Patch immediately- CVE-2021-3711 is a critical-severity vulnerability (CVSS 9.8 v3.1) affecting Active Iq Unified Manager (Netapp), Clustered Data Ontap (Netapp), Clustered Data Ontap Antivirus Connector (Netapp) and 22 more products.
- It is not listed in any known-exploited vulnerabilities catalog. No public exploit code is known.
- EPSS estimates a 88% probability of exploitation in the next 30 days.
- Fixed versions are available, including ansible 2.9.27-159000.3.9.1, ansible-doc 2.9.27-159000.3.9.1, dracut-saltboot 0.1.1665997480.587fa10-150000.1.41.1.
- Brandefense priority: patch immediately, because it is very likely to be exploited soon.
CVSS v3.1
9.8
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS (30-day exploit likelihood)
88%
Higher than 99.7% of all scored CVEs
Exploited in the wild
No known
Not in a known-exploited catalog
Public exploit code
None known
Get the full CVE-2021-3711 brief as a PDF
Every affected product and fixed release, exploitation status and a first 24 hours response checklist, emailed within minutes.
Description
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 62 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. Fixed in OpenSSL 1.1.1l (Affected 1.1.1-1.1.1k).
Affected Products
459 affected entries in total| Product | Affected versions | Fixed in |
|---|---|---|
| Active Iq Unified ManagerNetapp | See advisory | n/a |
| Clustered Data OntapNetapp | See advisory | n/a |
| Clustered Data Ontap Antivirus ConnectorNetapp | See advisory | n/a |
| E-Series Santricity OS ControllerNetapp | See advisory | 11.50.2 |
| Hci Management NodeNetapp | See advisory | n/a |
Patched Releases
ansible
2.9.27-159000.3.9.1
ansible-doc
2.9.27-159000.3.9.1
dracut-saltboot
0.1.1665997480.587fa10-150000.1.41.1, 0.1.1681904360.84ef141-159000.3.30.1
edk2
20240223gitedc6681206c1-1
firewalld-prometheus-config
0.1-159000.6.33.1
golang-github-boynux-squid_exporter
1.6-1.9.1, 1.6-150000.1.9.1, 1.6-159000.4.9.1, 1.6-4.9.2
golang-github-lusitaniae-apache_exporter
1.0.0-159000.4.12.1, 1.0.0-4.12.4
golang-github-prometheus-alertmanager
0.23.0-1.12.3, 0.26.0-4.12.4
golang-github-prometheus-node_exporter
1.3.0-1.15.3, 1.5.0-4.15.4
golang-github-prometheus-prometheus
2.45.0-159000.6.33.1, 2.45.0-4.33.3
golang-github-prometheus-promu
0.13.0-150000.3.9.1, 0.14.0-4.12.2
golang-github-QubitProducts-exporter_exporter
0.4.0-1.6.1, 0.4.0-159000.4.6.1, 0.4.0-4.6.2
grafana
8.3.4-1.1, 8.3.5-1.30.3, 8.3.5-150000.1.30.1, 8.3.5-150200.3.21.1, 8.5.13-1.36.2, 8.5.13-150000.1.36.3, 8.5.13-150100.3.12.1, 8.5.13-150200.3.29.5, 9.5.8-159000.4.24.1, 9.5.8-4.21.2
grype
0.92.1-1.1
grype-bash-completion
0.92.1-1.1
grype-fish-completion
0.92.1-1.1
grype-zsh-completion
0.92.1-1.1
kiwi-desc-saltboot
0.1.1687520761.cefb248-4.15.2
lib32-openssl
1:1.1.1.l-1
libopenssl-1_1-devel
1.1.1d-11.27.1, 1.1.1d-2.36.2, 1.1.1d-lp152.7.21.1, 1.1.1l-1.2
libopenssl-1_1-devel-32bit
1.1.1d-11.27.1, 1.1.1d-2.36.2, 1.1.1d-lp152.7.21.1, 1.1.1l-1.2
libopenssl1_1
1.1.1d-11.27.1, 1.1.1d-2.36.2, 1.1.1d-lp152.7.21.1, 1.1.1l-1.2
libopenssl1_1-32bit
1.1.1d-11.27.1, 1.1.1d-2.36.2, 1.1.1d-lp152.7.21.1, 1.1.1l-1.2
libopenssl1_1-hmac
1.1.1d-11.27.1, 1.1.1d-lp152.7.21.1, 1.1.1l-1.2
libopenssl1_1-hmac-32bit
1.1.1d-11.27.1, 1.1.1d-lp152.7.21.1
Timeline
Publicly disclosed
Mar 11, 2022
Last updated
Oct 10, 2026
Weakness Type
- CWE-120 Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')
- CWE-787 Out-of-bounds Write
References
- advisoryhttp://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-27221
- advisoryhttp://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-20509
- advisoryhttp://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-38882
- advisoryhttps://bugzilla.suse.com/1047218
- advisoryhttps://bugzilla.suse.com/1172110
FAQ
Common Questions.
In order to decrypt SM2 encrypted data an application is expected to call the API function EVP_PKEY_decrypt().
Affected: Active Iq Unified Manager (Netapp); Clustered Data Ontap (Netapp); Clustered Data Ontap Antivirus Connector (Netapp), among others. The full list is in the CVE brief.
It is not listed in any known-exploited vulnerabilities catalog.
No, it is not currently listed in the CISA Known Exploited Vulnerabilities catalog.
No public exploit code is known.
Fixed versions are available, including ansible 2.9.27-159000.3.9.1, ansible-doc 2.9.27-159000.3.9.1, dracut-saltboot 0.1.1665997480.587fa10-150000.1.41.1.
Brandefense priority: patch immediately, because it is very likely to be exploited soon.
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