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Full vulnerability report · 2021
CVE-2021-20197High confidence

There is an open race window when writing output in the following utilities in GNU binutils version 2.35 and earlier:ar, objcopy, strip, ranlib

Unknown · binutils

6.3MediumCVSS 3.1
Recommended action
Scheduled

Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority.

Patch available
R
Operational reassessment

Published severity in operational context

Open reassessment dashboard →
Published severityMediumOperational priority:Low, lowered one band.downgradedsince 3 Dec 2025

Evidence used

  • No CISA KEV confirmation is currently recorded.
  • Exploitation requires an existing local or physical foothold with privileges.
  • EPSS is 0.30% for the current model date.

Compensating controls

  • Validate the affected product branch and deploy the verified fixed release.
  • Restrict local access and enforce least privilege on affected hosts.
  • Monitor vendor guidance and exploitation sources for a material change.

Verification

  1. Confirm that the asset runs Unknown binutils and falls inside the recorded affected range.
  2. Verify the installed build against the product-specific fixed version after deployment.
  3. Validate exposure, authentication requirements and compensating controls in the actual environment.
  4. Reopen this reassessment when CVSS, KEV, EPSS, exploit evidence or remediation changes.
Mitigation target: No default targetRemediation target: Normal maintenance

This automated reassessment organises public evidence. It does not know asset exposure, business impact or control effectiveness and does not replace CVSS or a human risk decision.

Distribution package intelligence

Release-specific package status

Debian findings are scoped to the named distribution, release and source package. An absent finding does not mean a package is unaffected.

4 package states
Repository candidate not checked

A published vendor fix does not prove that a matching update is enabled and installable on a particular asset. Confirm the local package candidate before scheduling remediation.

Distribution releaseSource packageVendor stateFixed versionEvidence
Debian trixietrixie · sourcebinutilsVendor fix publishedDebian records a fixed source-package version for this release.2.37-3Debian Security Tracker ↗Source updated 24 Oct 2026
Debian bookwormbookworm · sourcebinutilsVendor fix publishedDebian records a fixed source-package version for this release.2.37-3Debian Security Tracker ↗Source updated 24 Oct 2026
Debian forkyforky · sourcebinutilsVendor fix publishedDebian records a fixed source-package version for this release.2.37-3Debian Security Tracker ↗Source updated 24 Oct 2026
Debian sidsid · sourcebinutilsVendor fix publishedDebian records a fixed source-package version for this release.2.37-3Debian Security Tracker ↗Source updated 24 Oct 2026
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
CVE-2021-20197 · CSAF 2.0 · revision 55 · interimSUSE Product Security TeamCVE-2021-20197
16 known affected

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

  • binutils as component of SUSE Linux Enterprise Server 11 SP1 for Teradata
  • SLES 15 SP1 CHOST Images for Amazon EC2
  • SLES 15 SP2 CHOST Images for Amazon EC2
  • SLES 15 SP3 CHOST Images for Amazon EC2
  • SLES 15 SP4 CHOST Images for Amazon EC2
  • SLES 15 SP5 CHOST Images for Amazon EC2
  • SLES 15 SP1 CHOST Images for Google
  • SLES 15 SP2 CHOST Images for Google
  • SLES 15 SP3 CHOST Images for Google
  • SLES 15 SP4 CHOST Images for Google
  • SLES 15 SP5 CHOST Images for Google
  • SLES 15 SP1 CHOST Images for Microsoft Azure
Summary
There is an open race window when writing output in the following utilities in GNU binutils version 2.35 and earlier:ar, objcopy, strip, ranlib. When these utilities are run as a privileged user (presumably as part of a script updating binaries across different users), an unprivileged user can trick these utilities into getting ownership of arbitrary files through a symlink.
Remediation
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
Optional official sources

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

Choose official national sources for this report. Each advisory shows its original language. Your selection is remembered on this device and included in shared links.

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-2021-7643

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 actionScheduled

Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority.

Patch available
01

What, why and how

There is an open race window when writing output in the following utilities in GNU binutils version 2.35 and earlier:ar, objcopy, strip, ranlib. When these utilities are run as a privileged user (presumably as part of a script updating binaries across different users), an unprivileged user can trick these utilities into getting ownership of arbitrary files through a symlink.

What

There is an open race window when writing output in the following utilities in GNU binutils version 2.35 and earlier:ar, objcopy, strip, ranlib. When these utilities are run as a privileged user (presumably as part of a script updating binaries across different users), an unprivileged user can trick these utilities into getting ownership of arbitrary files through a symlink.

Why

The product attempts to access a file based on the filename, but it does not properly prevent that filename from identifying a link or shortcut that resolves to an unintended resource.

How

An attacker operating through local access may attempt exploitation with low privileges. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

What

There is an open race window when writing output in the following utilities in GNU binutils version 2.35 and earlier:ar, objcopy, strip, ranlib. When these utilities are run as a privileged user (presumably as part of a script updating binaries across different users), an unprivileged user can trick these utilities into getting ownership of arbitrary files through a symlink.

Why

The product attempts to access a file based on the filename, but it does not properly prevent that filename from identifying a link or shortcut that resolves to an unintended resource.

How

An attacker operating through local access may attempt exploitation with low privileges. 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
local access → Improper Link Resolution Before File Access ('Link Following') → cause the confidentiality, integrity or availability impact described by the vendor
Attack surface
Local
Privileges required
Low: a basic authenticated account is required
User interaction
None
Attack complexity
High: exploitation depends on specific conditions
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-59 ↗

CWE-59: Improper Link Resolution Before File Access ('Link Following'). The product attempts to access a file based on the filename, but it does not properly prevent that filename from identifying a link or shortcut that resolves to an unintended resource.

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

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

AVLocalAttack vector: The attacker needs local access to the vulnerable system.ACHighAttack complexity: Successful exploitation depends on specific conditions outside the attacker's direct control.PRLowPrivileges required: The attacker needs basic user-level privileges.UINoneUser interaction: No action by another user is required.SUnchangedScope: The security impact remains within the vulnerable component's authority.CHighConfidentiality impact: A successful attack can cause a major loss.IHighIntegrity impact: A successful attack can cause a major loss.ANoneAvailability impact: No direct loss is represented by this metric.
Post-exploitation / living off the land
The issue can support a local privilege or sandbox boundary transition; normal system utilities may then be available in the gained context.
CWE-59
A

Official authority intelligence

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

Cyber Security Agency of Singapore · English · CSA-SB-20210331Security Bulletin 31 Mar 2021

The Cyber Security Agency of Singapore included this CVE in its official Security Bulletin 31 Mar 2021, published on 31 March 2021. Open the linked bulletin for the product, severity and reference information published in that issue.

Official advisory ↗
CERT-FR · French · CERTFR-2026-AVI-0218Multiples vulnérabilités dans les produits VMware

ecord?id=CVE-2020-12723 Référence CVE CVE-2020-12762 https://www.cve.org/CVERecord?id=CVE-2020-12762 Référence CVE CVE-2020-16599 https://www.cve.org/CVERecord?id=CVE-2020-16599 Référence CVE CVE-2020-1752 https://www.cve.org/CVERecord?id=CVE-2020-1752 Référence CVE CVE-2020-19726 https://www.cve.org/CVERecord?id=CVE-2020-19726 Référence CVE CVE-2020-22916 https://www.cve.org/CVERecord?id=CVE-2020-22916 Référence CVE CVE-2020-27618 https://www.cve.org/CVERecord?id=CVE-2020-27618 Référence CVE CVE-2020-29562 https://www.cve.org/CVERecord?id=CVE-2020-29562 Référence CVE CVE-2020-2981 https://www.cve.org/CVERecord?id=CVE-2020-2981 Référence CVE CVE-2021-20197 https://www.cve.org/CVERecord?id=CVE-2021-20197 Référence CVE CVE-2021-20205 https://www.cve.org/CVERecord?id=CVE-2021-20205 Référence CVE CVE-2021-20266 https://www.cve.org/CVERecord?id=CVE-2021-20266 Référence CVE CVE-2021-20284 https://www.cve.org/CVERecord?id=CVE-2021-20284 Référence CVE CVE-2021-22897 https://www.cve.org/CVERecord?id=CVE-2021-22897 Référence CVE CVE-2021-22898 https://www.cve.org/CVERecord?id=CVE-2021-22898 Référence CVE CVE-2021-22901 https://www.cve.org/CVERecord?id=CVE-2021-22901 Référence CVE CVE-2021-22922 https://www.cve.org/CVERecord?id=CVE-2021-22922 Référence CVE CVE-2021-22923 https://www.cve.org/CVERecord?id=

Official advisory ↗
CERT-FR · French · CERTFR-2025-AVI-0693Multiples vulnérabilités dans VMware Tanzu

etin de sécurité VMware 36036 du 14 août 2025 https://support.broadcom.com/web/ecx/support-content-notification/-/external/content/SecurityAdvisories/0/36036 Bulletin de sécurité VMware 36037 du 14 août 2025 https://support.broadcom.com/web/ecx/support-content-notification/-/external/content/SecurityAdvisories/0/36037 Bulletin de sécurité VMware 36038 du 14 août 2025 https://support.broadcom.com/web/ecx/support-content-notification/-/external/content/SecurityAdvisories/0/36038 Référence CVE CVE-2019-12900 https://www.cve.org/CVERecord?id=CVE-2019-12900 Référence CVE CVE-2020-11023 https://www.cve.org/CVERecord?id=CVE-2020-11023 Référence CVE CVE-2021-20197 https://www.cve.org/CVERecord?id=CVE-2021-20197 Référence CVE CVE-2021-32256 https://www.cve.org/CVERecord?id=CVE-2021-32256 Référence CVE CVE-2021-3572 https://www.cve.org/CVERecord?id=CVE-2021-3572 Référence CVE CVE-2021-3826 https://www.cve.org/CVERecord?id=CVE-2021-3826 Référence CVE CVE-2021-3927 https://www.cve.org/CVERecord?id=CVE-2021-3927 Référence CVE CVE-2021-3928 https://www.cve.org/CVERecord?id=CVE-2021-3928 Référence CVE CVE-2021-3968 https://www.cve.org/CVERecord?id=CVE-2021-3968 Référence CVE CVE-2021-3973 https://www.cve.org/CVERecord?id=CVE-2021-3973 Référence CVE CVE-2021-3974 https://www.cve.org/CVERecord?id=CVE-2021-3974

Official advisory ↗
JVN iPedia · Japanese · JVNDB-2021-004898GNU binutils におけるリンク解釈に関する脆弱性

GNU binutils には、リンク解釈に関する脆弱性が存在します。

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
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
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
Workaround
No verified workaround is recorded. Limit untrusted access and use least privilege until authoritative guidance is available.
04

Evidence and provenance

Published 26 Mar 2021 · Last source change 3 Dec 2025, 15:08 UTC · CWE-59 · Improper Link Resolution Before File Access ('Link Following')

CVE recordCVE.org · 5.2
CVSS sourceNIST NVD
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-2021-7643
Product sourceVendor CSAF · SUSE Product Security Team
Remediation sourceVendor CSAF · SUSE Product Security Team
CWE sourceCNA
NVD statusNVD modified after enrichment

Missing structured fields: affected product. Missing data is not evidence of low risk; review the primary advisory.

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-2021-7643↗Vendor CSAF · SUSE Product Security Team↗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-2021-20197 · cve.blacktree.nl