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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

n/a · 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
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-2021-7643

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.

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
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
binutils 2.35
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
Review the linked authoritative reference and apply the recorded fixed release appropriate to the affected product branch.
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 sourceCNA
Remediation sourceCVE/CNA references
CWE sourceCNA
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
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