Tar: tar: hidden file injection via crafted archives
Red Hat · Red Hat Enterprise Linux 10
5.0MediumCVSS 3.1
Recommended action
Within 7 days
Medium technical severity with public exploit material referenced by a structured source; prioritise exposed affected systems while verifying vendor guidance.
Patch available
Distribution package intelligence
Ubuntu vendor package status
Canonical’s release and source-package findings are shown separately from local repository availability.
1 package state
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.
Ubuntu release
Source package
Vendor state
Fixed version
Evidence
Ubuntu 24.04 LTSnoble · standard archive
tar
Vendor fix publishedCanonical reports that a fixed source package version has been published. Repository candidate availability is not checked by BlackTree.
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-2026-5704 · CSAF 2.0 · revision 3 · finalRed Hat Product Securitytar: tar: Hidden file injection via crafted archives
5 known affected
The vendor explicitly identifies these products as affected by this CVE.
tar.src as a component of Red Hat Enterprise Linux 6
tar.src as a component of Red Hat Enterprise Linux 7
tar as a component of Red Hat Enterprise Linux 8
tar.src as a component of Red Hat Enterprise Linux 8
tar.src as a component of Red Hat Hardened Images
Summary
A flaw was found in tar. A remote attacker could exploit this vulnerability by crafting a malicious archive, leading to hidden file injection with fully attacker-controlled content. This bypasses pre-extraction inspection mechanisms, potentially allowing an attacker to introduce malicious files onto a system without detection.
Remediation
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
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-2026-19317
No EUVD known-exploited evidence
A flaw was found in tar. A remote attacker could exploit this vulnerability by crafting a malicious archive, leading to hidden file injection with fully attacker-controlled content. This bypasses pre-extraction inspection mechanisms, potentially allowing an attacker to introduce malicious files onto a system without detection.
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
5.0 · CVSS 3.1
Advisory evidence
No linked advisory details stored yet
Recommended actionWithin 7 days
Medium technical severity with public exploit material referenced by a structured source; prioritise exposed affected systems while verifying vendor guidance.
Patch available
01
What, why and how
A flaw was found in tar. A remote attacker could exploit this vulnerability by crafting a malicious archive, leading to hidden file injection with fully attacker-controlled content. This bypasses pre-extraction inspection mechanisms, potentially allowing an attacker to introduce malicious files onto a system without detection.
What
A flaw was found in tar. A remote attacker could exploit this vulnerability by crafting a malicious archive, leading to hidden file injection with fully attacker-controlled content. This bypasses pre-extraction inspection mechanisms, potentially allowing an attacker to introduce malicious files onto a system without detection.
Why
The upload path does not sufficiently restrict the type, name, location or later execution of attacker-supplied files.
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
A flaw was found in tar. A remote attacker could exploit this vulnerability by crafting a malicious archive, leading to hidden file injection with fully attacker-controlled content. This bypasses pre-extraction inspection mechanisms, potentially allowing an attacker to introduce malicious files onto a system without detection.
Why
The upload path does not sufficiently restrict the type, name, location or later execution of attacker-supplied files.
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.Reference recorded
A structured CVE source labels at least one public reference as exploit material. BlackTree has not independently validated that it is safe, reliable or weaponised.
Likely attack path
local access → Unrestricted Upload of File with Dangerous Type → 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
Required interaction required
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-434: Unrestricted Upload of File with Dangerous Type. The product allows the upload or transfer of dangerous file types that are automatically processed within its environment.
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:L/PR:L/UI:R/S:U/C:N/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.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.PRLowPrivileges required: The attacker needs basic user-level privileges.UIRequiredUser interaction: Another user must perform an action for exploitation to succeed.SUnchangedScope: The security impact remains within the vulnerable component's authority.CNoneConfidentiality impact: No direct loss is represented by this metric.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-434Public exploit reference
A
Official authority intelligence
Only matched European and national findings are included. Language selectors and unavailable sources are omitted.
ENISA EUVD · EUVD-2026-19317Official EUVD mapping
A flaw was found in tar. A remote attacker could exploit this vulnerability by crafting a malicious archive, leading to hidden file injection with fully attacker-controlled content. This bypasses pre-extraction inspection mechanisms, potentially allowing an attacker to introduce malicious files onto a system without detection.
Official EUVD recordBSI · German · WID-SEC-W-2026-1057GNU tar: Schwachstelle ermöglicht Umgehen von Sicherheitsvorkehrungen
Ein lokaler Angreifer kann eine Schwachstelle in GNU tar ausnutzen, um Sicherheitsvorkehrungen zu umgehen.
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
tar.src as a component of Red Hat Enterprise Linux 6; tar.src as a component of Red Hat Enterprise Linux 7; tar as a component of Red Hat Enterprise Linux 8; tar.src as a component of Red Hat Enterprise Linux 8; tar.src as a component of Red Hat Hardened Images
Fixed
tar-2:1.35-13.el10_2.aarch64 as a component of Red Hat Enterprise Linux BaseOS (v. 10); tar-2:1.35-13.el10_2.ppc64le as a component of Red Hat Enterprise Linux BaseOS (v. 10); tar-2:1.35-13.el10_2.s390x as a component of Red Hat Enterprise Linux BaseOS (v. 10); tar-2:1.35-13.el10_2.src as a component of Red Hat Enterprise Linux BaseOS (v. 10); tar-2:1.35-13.el10_2.x86_64 as a component of Red Hat Enterprise Linux BaseOS (v. 10); tar-debuginfo-2:1.35-13.el10_2.aarch64 as a component of Red Hat Enterprise Linux BaseOS (v. 10); tar-debuginfo-2:1.35-13.el10_2.ppc64le as a component of Red Hat Enterprise Linux BaseOS (v. 10); tar-debuginfo-2:1.35-13.el10_2.s390x as a component of Red Hat Enterprise Linux BaseOS (v. 10); tar-debuginfo-2:1.35-13.el10_2.x86_64 as a component of Red Hat Enterprise Linux BaseOS (v. 10); tar-debugsource-2:1.35-13.el10_2.aarch64 as a component of Red Hat Enterprise Linux BaseOS (v. 10); tar-debugsource-2:1.35-13.el10_2.ppc64le as a component of Red Hat Enterprise Linux BaseOS (v. 10); tar-debugsource-2:1.35-13.el10_2.s390x as a component of Red Hat Enterprise Linux BaseOS (v. 10); tar-debugsource-2:1.35-13.el10_2.x86_64 as a component of Red Hat Enterprise Linux BaseOS (v. 10); tar-2:1.34-13.el9_8.aarch64 as a component of Red Hat Enterprise Linux BaseOS (v. 9); tar-2:1.34-13.el9_8.ppc64le as a component of Red Hat Enterprise Linux BaseOS (v. 9); tar-2:1.34-13.el9_8.s390x as a component of Red Hat Enterprise Linux BaseOS (v. 9); tar-2:1.34-13.el9_8.src as a component of Red Hat Enterprise Linux BaseOS (v. 9); tar-2:1.34-13.el9_8.x86_64 as a component of Red Hat Enterprise Linux BaseOS (v. 9); tar-debuginfo-2:1.34-13.el9_8.aarch64 as a component of Red Hat Enterprise Linux BaseOS (v. 9); tar-debuginfo-2:1.34-13.el9_8.ppc64le as a component of Red Hat Enterprise Linux BaseOS (v. 9); tar-debuginfo-2:1.34-13.el9_8.s390x as a component of Red Hat Enterprise Linux BaseOS (v. 9); tar-debuginfo-2:1.34-13.el9_8.x86_64 as a component of Red Hat Enterprise Linux BaseOS (v. 9); tar-debugsource-2:1.34-13.el9_8.aarch64 as a component of Red Hat Enterprise Linux BaseOS (v. 9); tar-debugsource-2:1.34-13.el9_8.ppc64le as a component of Red Hat Enterprise Linux BaseOS (v. 9); tar-debugsource-2:1.34-13.el9_8.s390x as a component of Red Hat Enterprise Linux BaseOS (v. 9); tar-debugsource-2:1.34-13.el9_8.x86_64 as a component of Red Hat Enterprise Linux BaseOS (v. 9); registry.redhat.io/discovery/discovery-server-rhel9@sha256:5efae8059c9c15454abac947b8482412686d60aaf5c104557d463e8282e340af_amd64 as a component of Red Hat Discovery 2; registry.redhat.io/discovery/discovery-server-rhel9@sha256:e9592a7aa5db3a61a7248d7b0305f3eb2fae189b1d078e483f1cc439f5b2351d_arm64 as a component of Red Hat Discovery 2
Action
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
Workaround
No verified workaround is recorded. Limit untrusted access and use least privilege until authoritative guidance is available.
04
Evidence and provenance
Published 6 Apr 2026 · Last source change 10 Sept 2026, 22:01 UTC · CWE-434 · Unrestricted Upload of File with Dangerous Type
CVE recordCVE.org · 5.2
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-2026-19317
Product sourceVendor CSAF · Red Hat Product Security
Remediation sourceVendor CSAF · Red Hat Product Security
CWE sourceCNA
NVD statusNVD modified after enrichment
Core structured fields are present and their contributing authorities are shown above.
Vendor guidanceAuthoritative vendor guidance changed from authoritative remediation link · vendor advisory to authoritative remediation link · vendor advisory.
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.
