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Full vulnerability report · 2022
CVE-2021-28544High confidence

Apache Subversion SVN authz protected copyfrom paths regression

Apache Software Foundation · Apache Subversion

4.3MediumCVSS 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
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-2021-15220

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

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

Apache Subversion SVN authz protected copyfrom paths regression Subversion servers reveal 'copyfrom' paths that should be hidden according to configured path-based authorization (authz) rules. When a node has been copied from a protected location, users with access to the copy can see the 'copyfrom' path of the original. This also reveals the fact that the node was copied. Only the 'copyfrom' path is revealed; not its contents. Both httpd and svnserve servers are vulnerable.

What

Apache Subversion SVN authz protected copyfrom paths regression Subversion servers reveal 'copyfrom' paths that should be hidden according to configured path-based authorization (authz) rules. When a node has been copied from a protected location, users with access to the copy can see the 'copyfrom' path of the original. This also reveals the fact that the node was copied. Only the 'copyfrom' path is revealed; not its contents. Both httpd and svnserve servers are vulnerable.

Why

The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information.

How

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

What

Apache Subversion SVN authz protected copyfrom paths regression Subversion servers reveal 'copyfrom' paths that should be hidden according to configured path-based authorization (authz) rules. When a node has been copied from a protected location, users with access to the copy can see the 'copyfrom' path of the original. This also reveals the fact that the node was copied. Only the 'copyfrom' path is revealed; not its contents. Both httpd and svnserve servers are vulnerable.

Why

The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information.

How

An attacker operating through a network path 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
a network path → Exposure of Sensitive Information to an Unauthorized Actor → cause the confidentiality, integrity or availability impact described by the vendor
Attack surface
Network
Privileges required
Low: a basic authenticated account is required
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-200 ↗

CWE-200: Exposure of Sensitive Information to an Unauthorized Actor. The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information.

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:L/UI:N/S:U/C:L/I:N/A:N

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.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.CLowConfidentiality impact: A successful attack can cause a limited loss.INoneIntegrity impact: No direct loss is represented by this metric.ANoneAvailability impact: No direct loss is represented by this metric.
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.
NetworkCWE-200Public exploit reference
A

Official authority intelligence

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

BSI · German · WID-SEC-W-2022-0778Apple macOS: Mehrere Schwachstellen

Ein Angreifer aus dem angrenzenden Netzwerk oder ein entfernter, anonymer, authentisierter oder lokaler Angreifer kann mehrere Schwachstellen in Apple macOS ausnutzen, um vertrauliche Informationen offenzulegen, seine Privilegien zu erweitern, Sicherheitsmaßnahmen zu umgehen, beliebigen Code auszuführen, Dateien zu manipulieren, einen Denial-of-Service-Zustand zu verursachen, Informationen falsch darzustellen und einen Cross-Site-Scripting-Angriff durchzuführen.

Official advisory
BSI · German · WID-SEC-W-2023-0561Xerox FreeFlow Print Server: Mehrere Schwachstellen

Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in Xerox FreeFlow Print Server ausnutzen, um die Vertraulichkeit, Verfügbarkeit und Integrität des Systems zu gefährden.

Official advisory
CERT-FR · French · CERTFR-2025-AVI-0969Multiples vulnérabilités dans les produits VMware

cord?id=CVE-2021-2369 Référence CVE CVE-2021-2388 https://www.cve.org/CVERecord?id=CVE-2021-2388 Référence CVE CVE-2021-24031 https://www.cve.org/CVERecord?id=CVE-2021-24031 Référence CVE CVE-2021-24032 https://www.cve.org/CVERecord?id=CVE-2021-24032 Référence CVE CVE-2021-25217 https://www.cve.org/CVERecord?id=CVE-2021-25217 Référence CVE CVE-2021-26260 https://www.cve.org/CVERecord?id=CVE-2021-26260 Référence CVE CVE-2021-26720 https://www.cve.org/CVERecord?id=CVE-2021-26720 Référence CVE CVE-2021-26945 https://www.cve.org/CVERecord?id=CVE-2021-26945 Référence CVE CVE-2021-27645 https://www.cve.org/CVERecord?id=CVE-2021-27645 Référence CVE CVE-2021-28544 https://www.cve.org/CVERecord?id=CVE-2021-28544 Référence CVE CVE-2021-28861 https://www.cve.org/CVERecord?id=CVE-2021-28861 Référence CVE CVE-2021-29921 https://www.cve.org/CVERecord?id=CVE-2021-29921 Référence CVE CVE-2021-29923 https://www.cve.org/CVERecord?id=CVE-2021-29923 Référence CVE CVE-2021-31566 https://www.cve.org/CVERecord?id=CVE-2021-31566 Référence CVE CVE-2021-31879 https://www.cve.org/CVERecord?id=CVE-2021-31879 Référence CVE CVE-2021-32256 https://www.cve.org/CVERecord?id=CVE-2021-32256 Référence CVE CVE-2021-32292 https://www.cve.org/CVERecord?id=CVE-2021-32292 Référence CVE CVE-2021-32490 https://www.cve.org/CVERecord?id=

Official advisory
CERT-FR · French · CERTFR-2022-AVI-665Multiples vulnérabilités dans les produits Apple

du 20 juillet 2022 https://support.apple.com/fr-fr/HT213340 Bulletin de sécurité Apple HT213341 du 20 juillet 2022 https://support.apple.com/fr-fr/HT213341 Bulletin de sécurité Apple HT213342 du 20 juillet 2022 https://support.apple.com/fr-fr/HT213342 Bulletin de sécurité Apple HT213343 du 20 juillet 2022 https://support.apple.com/fr-fr/HT213343 Bulletin de sécurité Apple HT213344 du 20 juillet 2022 https://support.apple.com/fr-fr/HT213344 Bulletin de sécurité Apple HT213345 du 20 juillet 2022 https://support.apple.com/fr-fr/HT213345 Bulletin de sécurité Apple HT213346 du 20 juillet 2022 https://support.apple.com/fr-fr/HT213346 Référence CVE CVE-2021-28544 https://www.cve.org/CVERecord?id=CVE-2021-28544 Référence CVE CVE-2021-4136 https://www.cve.org/CVERecord?id=CVE-2021-4136 Référence CVE CVE-2021-4166 https://www.cve.org/CVERecord?id=CVE-2021-4166 Référence CVE CVE-2021-4173 https://www.cve.org/CVERecord?id=CVE-2021-4173 Référence CVE CVE-2021-4187 https://www.cve.org/CVERecord?id=CVE-2021-4187 Référence CVE CVE-2021-4192 https://www.cve.org/CVERecord?id=CVE-2021-4192 Référence CVE CVE-2021-4193 https://www.cve.org/CVERecord?id=CVE-2021-4193 Référence CVE CVE-2021-46059 https://www.cve.org/CVERecord?id=CVE-2021-46059 Référence CVE CVE-2022-0128 https://www.cve.org/CVERecord?id=CVE-2022-0128

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
1.10.0 to 1.14.1
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. If business-safe, reduce exposure to the affected interface and allow only trusted sources until authoritative guidance is available.
04

Evidence and provenance

Published 12 Apr 2022 · Last source change 3 Aug 2024, 21:47 UTC · CWE-200 · Exposure of Sensitive Information to an Unauthorized Actor

CVE recordCVE.org · 5.1
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-2021-15220
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
CVE published
Fixed release or patch reference recorded
ENISA EUVD · EUVD-2021-15220↗Public exploit 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-2021-28544 · cve.blacktree.nl