CVE-2021-3712

mediumpriority · attend · 58EPSS 0.504 · 99 %ileexploit · PoCDEEUNLRUUS
grimoire priorityP1 · Urgent
Exploitable?
Public exploit
1 exploit · PoC
Likely / severe?
50.4% (99th) EPSS
CVSS 5.8 · medium
Is it mine?
984 products
Check your exposure
Who says so?
9 sources
cnnvd · enisa_euvd · fstec_bdu · osv

EPSS · scored 2026-10-23

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).

01

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

A vendor fix is available.

02

cvss

Technical severity, 0–10. One row per scoring source.

7.4
010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5.8–7.4

v2.05.8mediumAV:N/AC:M/Au:N/C:P/I:N/A:Pprimary · NVD / NIST USexploitability 8.6 · impact 4.9
v3.17.4highCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:Hprimary · NVD / NIST USexploitability 2.2 · impact 5.2
v3.07.4highCVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:Hsecondary · CISA US
v3.17.4highCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:Hsecondary · ENISA EU
v3.17.4highCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:Hsecondaryexploitability 2.2 · impact 5.2
v3.17.4highCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:Hsecondary · OSV
v3.17.4highCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:Hsecondary · Siemens ProductCERT DE
v3.17.4highCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:Hsecondary · Phoenix Contact PSIRT DE
v3.17.4highCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:H/E:Hsecondary · CVSS-BT (t0sche)
v3.17.4highCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:Hsecondary · NCSC-NL NL
v3.17.4highCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:Hsecondary · CISA US
v3.17.4highAV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:Hsecondary · FSTEC (BDU) RU
03

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Trackcoordinatorcisa_ssvcUS
04

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-125USprimaryCWE-125USCWE-125USCWE-125USCWE-125USCWE-125USCWE-125US
05

exploits (1)

Public proof-of-concept and weaponised exploit code.

06

affected products (984)

Products and version ranges known to be affected.

showing 20 of 984
07

advisories (24)

Vendor and ecosystem advisories describing this.

  • NCSC-2024-0239Kwetsbaarheden verholpen in Solarwinds PlatformNL2024-06-07csaf · ncsc_nlNL

    Solarwinds heeft kwetsbaarheden verholpen in Solarwinds Platform.

  • NCSC-2025-0336Kwetsbaarheden verholpen in Oracle HyperionNL2025-10-23csaf · ncsc_nlNL

    Oracle heeft meerdere kwetsbaarheden verholpen in Oracle Hyperion, waaronder Hyperion Financial Management en Hyperion Data Relationship Management.

  • NCSC-2026-0112Kwetsbaarheden verholpen in Siemens productenNL2026-04-14csaf · ncsc_nlNL

    Siemens heeft kwetsbaarheden verholpen in diverse producten zoals Analytics Toolkit, Ruggedcom, Industrial Edge Management Pro, SIDIS en TPM.

  • SSA-019200SSA-019200: Multiple Vulnerabilities in SCALANCE W-700 IEEE 802.11n Devices Before V6.6.02026-04-14csaf · siemens_psirtDE

    SCALANCE W-700 IEEE 802.11n family before V6.6.0 are affected by multiple vulnerabilities. Siemens has released a new version for SCALANCE W-700 IEEE 802.11n family and recommends to update to the latest version.

  • SSA-028723SSA-028723: Multiple OpenSSL Vulnerabilities in BFCClient Before V2.172025-08-12csaf · siemens_psirtDE

    Siemens BFCClient contains multiple vulnerabilities in the integrated OpenSSL component that could allow an attacker to read memory contents, to change the application behaviour or to create a denial of service condition. Siemens has released a new version for BFCClient and recommends to update to the latest version.

  • SSA-244969SSA-244969: OpenSSL Vulnerability in Industrial Products2022-02-08csaf · siemens_psirtDE

    OpenSSL has published a security advisory [0] about a vulnerability in OpenSSL versions 1.1.1 < 1.1.1l and 1.0.2 < 1.0.2za that allows an attacker to cause a denial of service (DoS) or to disclose private memory content. Siemens has released updates for several affected products and recommends to update to the latest versions. Siemens is preparing further updates and recommends countermeasures for products where updates are not, or not yet available. [0] https://www.openssl.org/news/secadv/20210824.txt

  • SSA-389290SSA-389290: Third-Party Component Vulnerabilities in SINEC INS2022-03-08csaf · siemens_psirtDE

    71 vulnerabilities in third-party components as Node.js, cURL, SQLite, CivetWeb and DNS(ISC BIND) could allow an attacker to interfere with the affected product in various ways. Siemens has released an update for SINEC INS and recommends to update to the latest versions.

  • VDE-2022-010PHOENIX CONTACT: Multiple Linux component vulnerabilities fixed in latest AXC F x152 LTS release2022-04-12csaf · phoenix_contact_psirtDE

    PLCnext Control AXC F x152 is certified according to IEC 62443-4-1 and IEC 62443-4-2. This certification requires that all third-party components used in the firmware are regularly checked for known vulnerabilities. Firmware components in version 2021.06 had already been updated. For the 2022.0 LTS version more firmware components have been updated implicitly fixing the vulnerabilities listed. The vulnerabilities listed above have not been individually verified in terms of actual impact and/or limitations in combination with the affected products listed. The current LTS release 2022.0 LTS contains updates of integrated third-party libraries, SDKs and other third-party software to address these issues nevertheless. UPDATE A (April 4th, 2022): Added RFC 4072 (Art. No. 1051328) and fixed affected version of AXC F 3152

  • WID-SEC-W-2022-0400OpenSSL: Mehrere Schwachstellen ermöglichen Denial of ServiceDeutsch2021-08-24csaf · cert_bundDE

    Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in OpenSSL ausnutzen, um einen Denial of Service Angriff durchzuführen oder Informationen offenzulegen.

  • WID-SEC-W-2022-0602IBM Security Verify Access: Mehrere SchwachstellenDeutsch2022-07-06csaf · cert_bundDE

    Ein entfernter anonymer, authentisierter oder lokaler Angreifer oder ein Angreifer aus dem angrenzenden Netzwerk kann mehrere Schwachstellen in IBM Security Verify Access ausnutzen, um einen Cross-Site-Scripting-Angriff durchzuführen, vertrauliche Informationen offenzulegen, seine Privilegien zu erweitern, Informationen zu manipulieren, einen Denial-of-Service-Zustand zu verursachen und Sicherheitsmaßnahmen zu umgehen.

  • WID-SEC-W-2023-0530Aruba ArubaOS: Mehrere SchwachstellenDeutsch2023-02-28csaf · cert_bundDE

    Ein entfernter, anonymer oder authentisierter Angreifer kann mehrere Schwachstellen in Aruba ArubaOS ausnutzen, um seine Privilegien zu erhöhen, Code zur Ausführung zu bringen, einen Cross Site Scripting Angriff durchzuführen, Informationen offenzulegen, Sicherheitsvorkehrungen zu umgehen oder einen Denial of Service zu verursachen.

  • WID-SEC-W-2023-1030Oracle Siebel CRM: Mehrere SchwachstellenDeutsch2023-04-18csaf · cert_bundDE

    Ein entfernter, anonymer oder authentisierter Angreifer kann mehrere Schwachstellen in Oracle Siebel CRM ausnutzen, um die Vertraulichkeit, Integrität und Verfügbarkeit zu gefährden.

  • WID-SEC-W-2024-0794Dell ECS: Mehrere SchwachstellenDeutsch2024-04-04csaf · cert_bundDE

    Ein Angreifer kann mehrere Schwachstellen in Dell ECS ausnutzen, um seine Privilegien zu erweitern, beliebigen Programmcode mit Administratorrechten auszuführen, Informationen offenzulegen, Dateien zu manipulieren, einen Cross-Site-Scripting-Angriff durchzuführen, Sicherheitsvorkehrungen zu umgehen oder einen Denial of Service Zustand herbeizuführen.

  • WID-SEC-W-2024-1186IBM DB2 REST: Mehrere SchwachstellenDeutsch2024-05-20csaf · cert_bundDE

    Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in IBM DB2 REST ausnutzen, um beliebigen Code auszuführen, Sicherheitsmaßnahmen zu umgehen oder einen Denial-of-Service-Zustand zu verursachen.

  • WID-SEC-W-2025-2366Oracle Hyperion: Mehrere SchwachstellenDeutsch2025-10-21csaf · cert_bundDE

    Ein entfernter, anonymer oder authentisierter Angreifer kann mehrere Schwachstellen in Oracle Hyperion ausnutzen, um die Vertraulichkeit, Integrität und Verfügbarkeit zu gefährden.

  • WID-SEC-W-2026-0180Dell Data Protection Advisor: Mehrere SchwachstellenDeutsch2026-01-20csaf · cert_bundDE

    Ein Angreifer kann mehrere Schwachstellen in Dell Data Protection Advisor ausnutzen, um beliebigen Code auszuführen, einen Denial-of-Service-Zustand zu erzeugen, Sicherheitsmaßnahmen zu umgehen und nicht näher spezifizierte Angriffe zu starten.

  • GHSA-q9wj-f4qw-6vfjRead buffer overruns processing ASN.1 strings2022-05-24ghsa · osvUS

    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 1.1.1j (Affected 1.1.1-1.1.1k). Fixed in OpenSSL 1.0.2za (Affected 1.0.2-1.0.2y).

  • ICSA-22-069-09Siemens SINEC INS2022-03-08icsa · cisa_csaf_otUS

    71 vulnerabilities in third-party components as Node.js, cURL, SQLite, CivetWeb and DNS(ISC BIND) could allow an attacker to interfere with the affected product in various ways. Siemens has released an update for SINEC INS and recommends to update to the latest versions.

  • ICSA-22-130-06Mitsubishi Electric MELSOFT GT OPC UA2022-05-10icsa · cisa_csaf_otUS

    Successful exploitation of these vulnerabilities could allow a remote attacker to send specially crafted messages, resulting in information disclosure or a denial-of-service condition.

  • ICSA-23-143-02Hitachi Energy's RTU500 Series Product (UPDATE B)2023-05-05icsa · cisa_csaf_otUS

    Successful exploitation of these vulnerabilities could allow an attacker to crash the device being accessed or cause a denial-of-service condition.

  • ICSA-25-226-21Siemens BFCClient2025-08-12icsa · cisa_csaf_otUS

    Siemens BFCClient contains multiple vulnerabilities in the integrated OpenSSL component that could allow an attacker to read memory contents, to change the application behaviour or to create a denial of service condition. Siemens has released a new version for BFCClient and recommends to update to the latest version.

  • ICSA-25-259-05Siemens OpenSSL Vulnerability in Industrial Products2022-02-08icsa · cisa_csaf_otUS

    OpenSSL has published a security advisory [0] about a vulnerability in OpenSSL versions 1.1.1 < 1.1.1l and 1.0.2 < 1.0.2za that allows an attacker to cause a denial of service (DoS) or to disclose private memory content. Siemens has released updates for several affected products and recommends to update to the latest versions. Siemens is preparing further updates and recommends countermeasures for products where updates are not, or not yet available. [0] https://www.openssl.org/news/secadv/20210824.txt

  • ICSA-26-111-07Siemens SCALANCE2026-04-14icsa · cisa_csaf_otUS

    SCALANCE W-700 IEEE 802.11n family before V6.6.0 are affected by multiple vulnerabilities. Siemens has released a new version for SCALANCE W-700 IEEE 802.11n family and recommends to update to the latest version.

  • RUSTSEC-2021-0098Read buffer overruns processing ASN.1 strings2021-08-24vendor · osvUS

    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 represented 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).

08

also known as (7)

Other names and identifiers for this entity.

09

sources

Which sources assert this record, and when.

cnnvdenisa_euvdfstec_bduosvcert_bundcisa_csaf_otncsc_nlsiemens_psirtphoenix_contact_psirtNVDCVE.orgMITRE
published 2021-08-24modified 2026-06-17
11

references (166)

External citations — patches, advisories, analysis.

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