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Full vulnerability report · 2021
CVE-2021-25215High confidence

An assertion check can fail while answering queries for DNAME records that require the DNAME to be processed to resolve itself

ISC · BIND9

7.5HighCVSS 3.1
Recommended action
Within 7 days

High technical severity; prioritise exposed affected systems while verifying vendor guidance.

Patch available
Direct vendor intelligence

Authoritative vendor CSAF and VEX advisories

Structured product status and remediation from the issuing vendor. Product-state explanations are always visible; large lists can be searched or downloaded.

1 current
SSA-389290 · CSAF 2.0 · revision 1 · finalSiemens ProductCERTSSA-389290: Third-Party Component Vulnerabilities in SINEC INS
1 known affected

The vendor explicitly identifies these products as affected by this CVE.

  • SINEC INS
Summary
In BIND 9.0.0 -> 9.11.29, 9.12.0 -> 9.16.13, and versions BIND 9.9.3-S1 -> 9.11.29-S1 and 9.16.8-S1 -> 9.16.13-S1 of BIND Supported Preview Edition, as well as release versions 9.17.0 -> 9.17.11 of the BIND 9.17 development branch, when a vulnerable version of named receives a query for a record triggering the flaw described above, the named process will terminate due to a failed assertion check. The vulnerability affects all currently maintained BIND 9 branches (9.11, 9.11-S, 9.16, 9.16-S, 9.17) as well as all other versions of BIND 9.
Remediation
Update to V1.0.1.1 or later version
Optional official sources

National CERT insights
?CERT means Computer Emergency Response Team; CSIRT is the closely related term Computer Security Incident Response Team.

Select the national-authority views to include. The exact source language is shown on each matched advisory. Your choice is remembered on this device and encoded in the shareable URL.

Official European source

ENISA European Vulnerability Database

Official EUVD identifiers, advisory evidence and known-exploited context. Missing fields are not treated as evidence of low risk.

1 current
ENISA EUVD identifier

EUVD-2021-12126

No EUVD known-exploited evidence

ENISA has published the identifier mapping but no EUVD description has been stored yet.

EUVD state
Present in the current official mapping
Known exploitation
Not present in the current ENISA EUVD known-exploited dataset. This is not proof of no exploitation.
ENISA score
Not supplied in the stored EUVD record
Advisory evidence
No linked advisory details stored yet
Recommended actionWithin 7 days

High technical severity; prioritise exposed affected systems while verifying vendor guidance.

Patch available
01

What, why and how

In BIND 9.0.0 -> 9.11.29, 9.12.0 -> 9.16.13, and versions BIND 9.9.3-S1 -> 9.11.29-S1 and 9.16.8-S1 -> 9.16.13-S1 of BIND Supported Preview Edition, as well as release versions 9.17.0 -> 9.17.11 of the BIND 9.17 development branch, when a vulnerable version of named receives a query for a record triggering the flaw described above, the named process will terminate due to a failed assertion check. The vulnerability affects all currently maintained BIND 9 branches (9.11, 9.11-S, 9.16, 9.16-S, 9.17) as well as all other versions of BIND 9.

What

In BIND 9.0.0 -> 9.11.29, 9.12.0 -> 9.16.13, and versions BIND 9.9.3-S1 -> 9.11.29-S1 and 9.16.8-S1 -> 9.16.13-S1 of BIND Supported Preview Edition, as well as release versions 9.17.0 -> 9.17.11 of the BIND 9.17 development branch, when a vulnerable version of named receives a query for a record triggering the flaw described above, the named process will terminate due to a failed assertion check. The vulnerability affects all currently maintained BIND 9 branches (9.11, 9.11-S, 9.16, 9.16-S, 9.17) as well as all other versions of BIND 9.

Why

The product contains an assert() or similar statement that can be triggered by an attacker, which leads to an application exit or other behavior that is more severe than necessary.

How

An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

What

In BIND 9.0.0 -> 9.11.29, 9.12.0 -> 9.16.13, and versions BIND 9.9.3-S1 -> 9.11.29-S1 and 9.16.8-S1 -> 9.16.13-S1 of BIND Supported Preview Edition, as well as release versions 9.17.0 -> 9.17.11 of the BIND 9.17 development branch, when a vulnerable version of named receives a query for a record triggering the flaw described above, the named process will terminate due to a failed assertion check. The vulnerability affects all currently maintained BIND 9 branches (9.11, 9.11-S, 9.16, 9.16-S, 9.17) as well as all other versions of BIND 9.

Why

The product contains an assert() or similar statement that can be triggered by an attacker, which leads to an application exit or other behavior that is more severe than necessary.

How

An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

02

Exploit reality and attack path

CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.

Observed exploitation
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
No confirmed evidence

No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.

Public PoC / exploit material
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
None recorded

No exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.

Likely attack path
a network path → Reachable Assertion → cause the confidentiality, integrity or availability impact described by the vendor
Attack surface
Network
Privileges required
None: unauthenticated exploitation is possible
User interaction
None
Attack complexity
Low: no specialised conditions are recorded
Security boundary
Unchanged: impact remains within the vulnerable component's security authority
Weakness
?CWE means Common Weakness Enumeration: a standard category for the underlying weakness.
CWE-617 ↗

CWE-617: Reachable Assertion. The product contains an assert() or similar statement that can be triggered by an attacker, which leads to an application exit or other behavior that is more severe than necessary.

CVSS vector
?CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Common Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.

AVNetworkAttack vector: The vulnerable component can be reached over a network.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.PRNonePrivileges required: The attacker does not need an account or existing privileges.UINoneUser interaction: No action by another user is required.SUnchangedScope: The security impact remains within the vulnerable component's authority.CNoneConfidentiality impact: No direct loss is represented by this metric.INoneIntegrity impact: No direct loss is represented by this metric.AHighAvailability impact: A successful attack can cause a major loss.
Post-exploitation / living off the land
No specific living-off-the-land technique is confirmed in the structured sources. Monitor normal administration tools for activity inconsistent with the affected service's baseline.
NetworkUnauthenticatedCWE-617
A

Official authority intelligence

Only matched European and national findings are included. Language selectors and unavailable sources are omitted.

BSI · German · WID-SEC-W-2025-2027Internet Systems Consortium BIND: Mehrere Schwachstellen ermöglichen Denial of Service

Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in Internet Systems Consortium BIND ausnutzen, um einen Denial of Service Angriff durchzuführen.

Official advisory
CERT-FR · French · CERTFR-2022-AVI-216Multiples vulnérabilités dans les produits Siemens

d?id=CVE-2021-23362 Référence CVE CVE-2021-23840 https://www.cve.org/CVERecord?id=CVE-2021-23840 Référence CVE CVE-2021-25173 https://www.cve.org/CVERecord?id=CVE-2021-25173 Référence CVE CVE-2021-25174 https://www.cve.org/CVERecord?id=CVE-2021-25174 Référence CVE CVE-2021-25175 https://www.cve.org/CVERecord?id=CVE-2021-25175 Référence CVE CVE-2021-25176 https://www.cve.org/CVERecord?id=CVE-2021-25176 Référence CVE CVE-2021-25177 https://www.cve.org/CVERecord?id=CVE-2021-25177 Référence CVE CVE-2021-25178 https://www.cve.org/CVERecord?id=CVE-2021-25178 Référence CVE CVE-2021-25214 https://www.cve.org/CVERecord?id=CVE-2021-25214 Référence CVE CVE-2021-25215 https://www.cve.org/CVERecord?id=CVE-2021-25215 Référence CVE CVE-2021-25216 https://www.cve.org/CVERecord?id=CVE-2021-25216 Référence CVE CVE-2021-25217 https://www.cve.org/CVERecord?id=CVE-2021-25217 Référence CVE CVE-2021-25219 https://www.cve.org/CVERecord?id=CVE-2021-25219 Référence CVE CVE-2021-27290 https://www.cve.org/CVERecord?id=CVE-2021-27290 Référence CVE CVE-2021-31344 https://www.cve.org/CVERecord?id=CVE-2021-31344 Référence CVE CVE-2021-31346 https://www.cve.org/CVERecord?id=CVE-2021-31346 Référence CVE CVE-2021-31784 https://www.cve.org/CVERecord?id=CVE-2021-31784 Référence CVE CVE-2021-31889 https://www.cve.org/CVERecord?id=

Official advisory
CERT-FR · French · CERTFR-2021-AVI-791Multiples vulnérabilités dans les produits IBM

CVERecord?id=CVE-2021-23336 Référence CVE CVE-2021-23337 https://www.cve.org/CVERecord?id=CVE-2021-23337 Référence CVE CVE-2021-23362 https://www.cve.org/CVERecord?id=CVE-2021-23362 Référence CVE CVE-2021-23364 https://www.cve.org/CVERecord?id=CVE-2021-23364 Référence CVE CVE-2021-2341 https://www.cve.org/CVERecord?id=CVE-2021-2341 Référence CVE CVE-2021-2369 https://www.cve.org/CVERecord?id=CVE-2021-2369 Référence CVE CVE-2021-2388 https://www.cve.org/CVERecord?id=CVE-2021-2388 Référence CVE CVE-2021-2432 https://www.cve.org/CVERecord?id=CVE-2021-2432 Référence CVE CVE-2021-25214 https://www.cve.org/CVERecord?id=CVE-2021-25214 Référence CVE CVE-2021-25215 https://www.cve.org/CVERecord?id=CVE-2021-25215 Référence CVE CVE-2021-27218 https://www.cve.org/CVERecord?id=CVE-2021-27218 Référence CVE CVE-2021-27219 https://www.cve.org/CVERecord?id=CVE-2021-27219 Référence CVE CVE-2021-27290 https://www.cve.org/CVERecord?id=CVE-2021-27290 Référence CVE CVE-2021-29679 https://www.cve.org/CVERecord?id=CVE-2021-29679 Référence CVE CVE-2021-29745 https://www.cve.org/CVERecord?id=CVE-2021-29745 Référence CVE CVE-2021-29894 https://www.cve.org/CVERecord?id=CVE-2021-29894 Référence CVE CVE-2021-30661 https://www.cve.org/CVERecord?id=CVE-2021-30661 Référence CVE CVE-2021-3177 https://www.cve.org/CVERecord?id=C

Official advisory
CERT-FR · French · CERTFR-2021-AVI-638Multiples vulnérabilités dans Juniper Junos Space

ecord?id=CVE-2020-25705 Référence CVE CVE-2020-28374 https://www.cve.org/CVERecord?id=CVE-2020-28374 Référence CVE CVE-2020-29573 https://www.cve.org/CVERecord?id=CVE-2020-29573 Référence CVE CVE-2020-29661 https://www.cve.org/CVERecord?id=CVE-2020-29661 Référence CVE CVE-2020-7053 https://www.cve.org/CVERecord?id=CVE-2020-7053 Référence CVE CVE-2021-20265 https://www.cve.org/CVERecord?id=CVE-2021-20265 Référence CVE CVE-2021-20277 https://www.cve.org/CVERecord?id=CVE-2021-20277 Référence CVE CVE-2021-20305 https://www.cve.org/CVERecord?id=CVE-2021-20305 Référence CVE CVE-2021-2163 https://www.cve.org/CVERecord?id=CVE-2021-2163 Référence CVE CVE-2021-25215 https://www.cve.org/CVERecord?id=CVE-2021-25215 Référence CVE CVE-2021-26937 https://www.cve.org/CVERecord?id=CVE-2021-26937 Référence CVE CVE-2021-27363 https://www.cve.org/CVERecord?id=CVE-2021-27363 Référence CVE CVE-2021-27364 https://www.cve.org/CVERecord?id=CVE-2021-27364 Référence CVE CVE-2021-27365 https://www.cve.org/CVERecord?id=CVE-2021-27365 Référence CVE CVE-2021-27803 https://www.cve.org/CVERecord?id=CVE-2021-27803 Gestion détaillée du document le 18 août 2021 Version initiale Alertes Avis Bulletins d’actualités Mentions légales Conditions générales À propos Contact cyber.gouv.fr service-public.fr legifrance.gouv.fr info.gouv.f

Official advisory
CERT-FR · French · CERTFR-2021-AVI-325Multiples vulnérabilités dans BIND

De multiples vulnérabilités ont été découvertes dans BIND. Elles permettent à un attaquant de provoquer une exécution de code arbitraire à distance, un déni de service à distance, une atteinte à l'intégrité des données et une atteinte à la confidentialité des données.

Official advisory
03

Patch and workaround

Operational remediation based on structured source evidence.

Status
?Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change.
Patch available
Affected
SINEC INS
Fixed
An authoritative update reference is available, but the fixed version is not recorded in the structured CVE fields. Check the linked vendor advisory for the applicable release.
Action
Update to V1.0.1.1 or later version
Workaround
No verified workaround is recorded. If business-safe, reduce exposure to the affected interface and allow only trusted sources until authoritative guidance is available.
04

Evidence and provenance

Published 29 Apr 2021 · Last source change 16 Sept 2024, 22:02 UTC · CWE-617 · Reachable Assertion

CVE recordCVE.org · 5.1
CVSS sourceCNA
EPSS source
?The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.
FIRST · tracked since 2026-08-14
European sourceENISA EUVD · EUVD-2021-12126
Product sourceVendor CSAF · Siemens ProductCERT
Remediation sourceVendor CSAF · Siemens ProductCERT
CWE sourceNIST NVD
NVD statusNVD modified after enrichment

Core structured fields are present and their contributing authorities are shown above.

Material change intelligence

What changed after publication

View recent updates →

No material field changes have been recorded since change tracking began. Routine source refreshes and cosmetic edits are intentionally excluded.

Material fields only · duplicate refreshes suppressed · history retained for the configured operational retention period
CVE published
Fixed release or patch reference recorded
ENISA EUVD · EUVD-2021-12126↗Patch or update reference↗CVE authority or vendor reference↗Patch or update reference↗Official CVE record (CNA and ADP data)↗NVD record↗
Technical terms and abbreviations used in this report
CVE
Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
CVSS
Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
EPSS
Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
CWE
Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
CNA
CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
CISA ADP
Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
NVD
National Vulnerability Database: NIST's enrichment service for CVE records.
CERT / CSIRT
A computer security incident response team that publishes warnings or coordinates incident response.
PoC
Proof of concept: public material that demonstrates or helps reproduce exploitation.
CSAF
Common Security Advisory Framework: a machine-readable format for security advisories.
LoTL
Living off the land: abuse of legitimate tools or system functions during an attack.
Free version - for non-commercial use only.CVE-2021-25215 · cve.blacktree.nl