kbrain

CVE-2021-3712

HIGH · CVSS 7.4EPSS 50.4%EU EUVD

ASN.1 strings are represented internally within OpenSSL as an ASN1_STRING structure which contains a buffer holding the string data and a field holding the buffer length. This contrasts with normal C strings which are repesented as a buffer for the string data which is terminated with a NUL (0) byte. Although not a strict requirement, ASN.1 strings that are parsed using OpenSSL's own "d2i" functions (and other similar parsing functions) as well as any string whose value has been set with the ASN1_STRING_set() function will additionally NUL terminate the byte array in the ASN1_STRING structure. However, it is possible for applications to directly construct valid ASN1_STRING structures which do not NUL terminate the byte array by directly setting the "data" and "length" fields in the ASN1_STRING array. This can also happen by using the ASN1_STRING_set0() function. Numerous OpenSSL functions that print ASN.1 data have been found to assume that the ASN1_STRING byte array will be NUL terminated, even though this is not guaranteed for strings that have been directly constructed. Where an application requests an ASN.1 structure to be printed, and where that ASN.1 structure contains ASN1_STRINGs that have been directly constructed by the application without NUL terminating the "data" field, then a read buffer overrun can occur. The same thing can also occur during name constraints processing of certificates (for example if a certificate has been directly constructed by the application instead of loading it via the OpenSSL parsing functions, and the certificate contains non NUL terminated ASN1_STRING structures). It can also occur in the X509_get1_email(), X509_REQ_get1_email() and X509_get1_ocsp() functions. If a malicious actor can cause an application to directly construct an ASN1_STRING and then process it through one of the affected OpenSSL functions then this issue could be hit. This might result in a crash (causing a Denial of Service attack). It could also result in the disclosure of private memory contents (such as private keys, or sensitive plaintext). Fixed in OpenSSL 1.1.1l (Affected 1.1.1-1.1.1k). Fixed in OpenSSL 1.0.2za (Affected 1.0.2-1.0.2y).

Key facts

CVSS score
7.4 (v3.1)
Severity
HIGH
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:H
Weakness (CWE)
CWE-125
EPSS score
50.4% (99th percentile)
In CISA KEV
No
In EU EUVD
Yes (EUVD-2022-4935)
Published
August 24, 2021
NVD last modified
June 17, 2026
Status
Modified

EU Vulnerability Database (EUVD)

This vulnerability is also tracked by ENISA as EUVD-2022-4935 in the EU Vulnerability Database. Last updated in EUVD on April 16, 2026.

View on the EU Vulnerability Database

Affected products

  • debian / debian linux
  • debian / debian linux
  • debian / debian linux
  • mcafee / epolicy orchestrator
  • mcafee / epolicy orchestrator
  • mcafee / epolicy orchestrator
  • mcafee / epolicy orchestrator
  • mcafee / epolicy orchestrator
  • mcafee / epolicy orchestrator
  • mcafee / epolicy orchestrator
  • mcafee / epolicy orchestrator
  • mcafee / epolicy orchestrator
  • mcafee / epolicy orchestrator
  • mcafee / epolicy orchestrator
  • mcafee / epolicy orchestrator
  • netapp / clustered data ontap
  • netapp / clustered data ontap antivirus connector
  • netapp / e-series santricity os controller
  • netapp / hci management node
  • netapp / manageability software development kit
  • netapp / santricity smi-s provider
  • netapp / solidfire
  • netapp / storage encryption
  • openssl / openssl
  • oracle / communications cloud native core console
  • oracle / communications cloud native core security edge protection proxy
  • oracle / communications cloud native core unified data repository
  • oracle / communications session border controller
  • oracle / communications session border controller
  • oracle / communications unified session manager
  • oracle / communications unified session manager
  • oracle / enterprise communications broker
  • oracle / enterprise communications broker
  • oracle / enterprise session border controller
  • oracle / enterprise session border controller
  • oracle / essbase
  • oracle / essbase
  • oracle / health sciences inform publisher
  • oracle / health sciences inform publisher
  • oracle / jd edwards enterpriseone tools
  • oracle / jd edwards world security
  • oracle / mysql connectors
  • oracle / mysql enterprise monitor
  • oracle / mysql server
  • oracle / mysql workbench
  • oracle / peoplesoft enterprise peopletools
  • oracle / peoplesoft enterprise peopletools
  • oracle / peoplesoft enterprise peopletools
  • oracle / secure backup
  • oracle / zfs storage appliance kit

and 3 more…

Certified products that may be affected

3 FIPS 140 or Common Criteria certified products, from automated matching by sec-certs.org.

References

Last updated September 17, 2026 · Source: NVD, CISA KEV, FIRST.org EPSS

Query CVEs from your AI assistant

The CVE/NVD Explorer brain answers CVE questions directly inside Claude, ChatGPT, or any MCP assistant — always up to date, no setup. Add it once and stop pasting advisories into chat.

Add the CVE brain