HighCVE-2026-54369

    acl < 2.4.0 Symlink Traversal Privilege Escalation via libacl Functions (CVE-2026-54369)

    Published Last modified Sources: BSI, Red Hat, CVE.org, Msrc Update Guide, SUSE

    Share

    What is affected, what to do

    A flaw was found in the `acl` package, specifically within its `libacl` pathname-based functions. A local attacker could exploit this vulnerability by using a symbolic link to replace a pathname component.

    Update Acl to version 2.4.0.

    Affected
    • Acl lt *..2.4.0
    Fixed in
    • Acl 2.4.0

    Not sure whether and how you are affected? Ask a question about this vulnerability

    Metrics

    8.4

    Priority

    XIEM Effective CVSS: highest available CVSS rating from NVD and vendor data.

    Source: NVD, CVSS v4

    7.1

    CVSS v3

    Severity High on the scale from 0 to 10.

    Source: BSI, Red Hat, CVE.org, Msrc Update Guide, SUSE

    0.2 %

    EPSS score

    Low — model estimates < 1% exploitation likelihood.

    Source: FIRST EPSS, percentile 4.5

    Show all metrics
    Severity
    High
    Priority (0–325)

    The priority score is a consolidated metric that condenses several individual signals into a single, action-guiding ranking: technical severity (CVSS), exploitation likelihood (EPSS), known-exploited status (KEV) and the context of the affected asset. The aim is to answer the only truly important question in vulnerability management: what first?

    Read in glossary
    61.44 Methodology
    Exploit maturity

    An exploit is code or a technique that specifically uses a concrete vulnerability to force unintended behaviour — such as executing code or escalating privileges. It is the tool that turns a theoretical flaw into a practical attack.

    Read in glossary
    no public PoC known
    XIEM Effective CVSS

    XIEM® is the tiered managed-security operating model from NEOSEC and a registered trademark of NEOSEC GmbH. It extends classic SIEM — the central collection, normalisation and correlation of security-relevant events — with endpoint forensics, network visibility and deception technology, and consolidates them into three building tiers: Sentry, Orchestrate and Command.

    Read in glossary
    8.4 Methodology
    CVSS v3

    CVSS is the globally established, open standard for assessing the technical severity of a vulnerability on a scale from 0 to 10. It describes how easily a flaw can be exploited and what damage it can cause — but not how likely its actual exploitation is. CVSS and the complementary EPSS deliberately answer different questions.

    Read in glossary
    7.1
    CVSS v4

    CVSS is the globally established, open standard for assessing the technical severity of a vulnerability on a scale from 0 to 10. It describes how easily a flaw can be exploited and what damage it can cause — but not how likely its actual exploitation is. CVSS and the complementary EPSS deliberately answer different questions.

    Read in glossary
    8.4
    EPSS score

    The EPSS score is the absolute model output for an individual vulnerability: the estimated probability of real-world exploitation within the next 30 days, expressed as a value between 0 and 1 (i.e. 0 % to 100 %). A score of 0.42 means „the model estimates a 42 % chance of real-world exploitation within 30 days“.

    Read in glossary
    0.2 %
    Low — model estimates < 1% exploitation likelihood.
    EPSS percentile

    The EPSS percentile is the relative position of a vulnerability within all EPSS-scored CVEs, expressed as a value between 0 and 1. A percentile of 0.90 means „this CVE has a higher EPSS score than 90 % of all other scored CVEs“. Unlike the EPSS score, it is not a probability — but a positioning within a ranking.

    Read in glossary
    4.5
    Low — this CVE sits in the lower 10% of all CVEs scored today.
    KEV status

    The KEV catalogue is a list maintained by the US authority CISA of vulnerabilities for which active exploitation in the wild has been confirmed. It answers not the question „how severe?“ but „is it already being attacked?“ — thereby sharply prioritising patching.

    Read in glossary
    —
    Published
    CISA assessment (SSVC)
    Exploitation: none known · not automatable · Technical impact: total
    Source: CISA Vulnrichment, as of 29 June 2026
    CWE

    CWE is a catalogue of typical weakness types in software and hardware — such as flawed input validation, unsafe memory handling or poor authentication. Where a CVE names a concrete vulnerability in a concrete product, a CWE describes the underlying class of defect.

    Read in glossary
    CWE-59, CWE-59

    Detection rules

    No NEOSEC detection rule is available for this vulnerability yet.

    Classification under NIS2 and CRA

    Rule-based classification from exploitation status and severity. It does not replace a case-by-case assessment.

    NIS2

    NIS2 is EU Directive (EU) 2022/2555 to raise the level of cybersecurity across the Union. It substantially broadens obligations compared with the first NIS directive: more sectors, mandatory risk management, staged reporting duties and personal accountability of senior management.

    Read in glossary
    High technical severity: assess and remediate the vulnerability in vulnerability handling under Art. 21(2)(e) NIS2 and document the decision.
    CRA

    The CRA is EU Regulation (EU) 2024/2847 setting horizontal cybersecurity requirements for „products with digital elements“ — from industrial controllers and software to connected consumer devices. For the first time manufacturers must ensure security across the entire product lifecycle, handle vulnerabilities and provide security updates.

    Read in glossary
    From 11.12.2027, Annex I Part II CRA requires manufacturers of affected products with digital elements to handle vulnerabilities without delay and provide security updates.
    ISO/IEC 27001

    ISO/IEC 27001 is the internationally leading standard for an information security management system (ISMS). It describes a risk-based, process-oriented framework to systematically plan, implement, review and improve information security.

    Read in glossary
    Control A.8.8, management of technical vulnerabilities: assess relevance to your systems, plan remediation and keep evidence.

    Description

    A flaw was found in the `acl` package, specifically within its `libacl` pathname-based functions. A local attacker could exploit this vulnerability by using a symbolic link to replace a pathname component. This could allow the attacker to redirect access control list (ACL) read or write operations to arbitrary files or directories, leading to unauthorized manipulation of ACLs and ultimately local privilege escalation.

    Source: BSI WID Portal, BSI CSAF, redhat_csaf, NVD (NIST), CVE.org (MITRE), Microsoft Security Update Guide, suse_csaf, cvelistv5

    Affected products

    The following versions are affected. Older releases of the same product line are also vulnerable unless stated otherwise.

    Affected products
    Affected versionsFixed in
    acl projectacl
    • < 2.4.0
    • 2.4.0
    IBMApp Connect Enterprise CD
    • < 13.4.0
    • 13.4.0
    IBMApp Connect Enterprise LTS
    • < 13.4.0
    • < 12.0.26
    • 13.4.0
    • 12.0.26
    IBMQRadar SIEM
    • <7.5.0 UP15 IF06
    • —
    OracleCommunications
    • 7.5.0
    • 15.0.1.0.0
    • 26.1.202
    • 7.7.0
    • 25.1.100
    • 47.0.0.2.0
    • 7.0.0
    • 6
    • 6.1
    • 7.8.0
    • 24.2.4-25.2.000
    • 7.5.1
    • 25.2.100
    • 8.0-8.1
    • 8.0.1
    • 7.6.0
    • 14
    • 15.1.0.0.0
    • 25.1.200
    • 6.1.1-7.0.0
    • 25.2.200
    • 15.2.0.0.0
    • 11
    • 26.1.200
    • 25.2.202
    • 25.2.201
    • 15.0.0.0.0
    • 8.0-8.3
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    Red HatEnterprise Linux
    • 9
    • 10
    • —
    • —

    Vendors and products

    Weakness classes (CWE)

    • CWE-59Improper Link Resolution Before File Access ('Link Following')

      Base

      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.

      Entry at MITRE CWE-59

    • CWE-59Improper Link Resolution Before File Access ('Link Following')

      Base

      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.

      Entry at MITRE CWE-59

    References & sources

    Changes to this CVE

    Who changed this CVE and when: NVD (analysis, affected products, CVSS), the CVE publisher (CNA) and additional providers such as CISA (ADP).

    1. Record modifiedRed Hat ADP

      Show 3 original changes
      Individual changes of this event as published by NVD
      TypeActionBeforeAfter
      Referenceadded
      —
      https://access.redhat.com/errata/RHSA-2026:67140
      Referenceadded
      —
      https://access.redhat.com/errata/RHSA-2026:67142
      Referenceadded
      —
      https://access.redhat.com/errata/RHSA-2026:67144

      Source identifier: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c

    2. Record modifiedRed Hat ADP

      Show 2 original changes
      Individual changes of this event as published by NVD
      TypeActionBeforeAfter
      Affected versions (publisher)added
      —
      Affected value modified. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/54xxx/CVE-2026-54369.json">CVE-2026-54369</a>
      Referenceadded
      —
      https://access.redhat.com/errata/RHSA-2026:64805

      Source identifier: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c

    3. Record modifiedRed Hat ADP

      1 individual change: Affected versions (publisher)

      Show the original change
      Individual changes of this event as published by NVD
      TypeActionBeforeAfter
      Affected versions (publisher)added
      —
      Affected value modified. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/54xxx/CVE-2026-54369.json">CVE-2026-54369</a>

      Source identifier: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c

    4. Record modifiedVulnCheck

      Show 6 original changes
      Individual changes of this event as published by NVD
      TypeActionBeforeAfter
      Referenceadded
      —
      https://cgit.git.savannah.nongnu.org/cgit/acl.git/commit/?id=24a227d0ab8576612194f8a56c2314389adc74a5
      Referenceadded
      —
      https://cgit.git.savannah.nongnu.org/cgit/acl.git/commit/?id=3589787cd589b34bdd9265936e17190b6d3f17d1
      Referenceadded
      —
      https://www.vulncheck.com/advisories/acl-symlink-traversal-privilege-escalation-via-libacl-functions
      Referenceremoved
      https://cgit.git.savannah.nongnu.org/cgit/acl.git/commit/?id=24a227d0ab8576612194f8a56c2314389adc74a5
      —
      Referenceremoved
      https://cgit.git.savannah.nongnu.org/cgit/acl.git/commit/?id=3589787cd589b34bdd9265936e17190b6d3f17d1
      —
      Referenceremoved
      https://www.vulncheck.com/advisories/acl-symlink-traversal-privilege-escalation-via-libacl-functions
      —

      Source identifier: disclosure@vulncheck.com

    5. Record modifiedRed Hat ADP

      Show 27 original changes
      Individual changes of this event as published by NVD
      TypeActionBeforeAfter
      Affected versions (publisher)added
      —
      Affected value modified. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/54xxx/CVE-2026-54369.json">CVE-2026-54369</a>
      Referenceadded
      —
      https://access.redhat.com/errata/RHSA-2026:34351
      Referenceadded
      —
      https://access.redhat.com/errata/RHSA-2026:42736
      Referenceadded
      —
      https://access.redhat.com/errata/RHSA-2026:42739
      Referenceadded
      —
      https://access.redhat.com/errata/RHSA-2026:43420
      Referenceadded
      —
      https://access.redhat.com/errata/RHSA-2026:44481
      Referenceadded
      —
      https://access.redhat.com/errata/RHSA-2026:46836
      Referenceadded
      —
      https://access.redhat.com/errata/RHSA-2026:50205
      Referenceadded
      —
      https://access.redhat.com/errata/RHSA-2026:53371
      Referenceadded
      —
      https://access.redhat.com/errata/RHSA-2026:54769
      Referenceadded
      —
      https://access.redhat.com/errata/RHSA-2026:58981
      Referenceadded
      —
      https://access.redhat.com/security/cve/CVE-2026-54369
      Referenceadded
      —
      https://bugzilla.redhat.com/show_bug.cgi?id=2490277
      Referenceadded
      —
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-54369.json
      Referenceremoved
      https://access.redhat.com/errata/RHSA-2026:34351
      —
      Referenceremoved
      https://access.redhat.com/errata/RHSA-2026:42736
      —
      Referenceremoved
      https://access.redhat.com/errata/RHSA-2026:42739
      —
      Referenceremoved
      https://access.redhat.com/errata/RHSA-2026:43420
      —
      Referenceremoved
      https://access.redhat.com/errata/RHSA-2026:44481
      —
      Referenceremoved
      https://access.redhat.com/errata/RHSA-2026:46836
      —
      Referenceremoved
      https://access.redhat.com/errata/RHSA-2026:50205
      —
      Referenceremoved
      https://access.redhat.com/errata/RHSA-2026:53371
      —
      Referenceremoved
      https://access.redhat.com/errata/RHSA-2026:54769
      —
      Referenceremoved
      https://access.redhat.com/errata/RHSA-2026:58981
      —
      Referenceremoved
      https://access.redhat.com/security/cve/CVE-2026-54369
      —
      Referenceremoved
      https://bugzilla.redhat.com/show_bug.cgi?id=2490277
      —
      Referenceremoved
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-54369.json
      —

      Source identifier: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c

    Show 11 older changes

    1. Record modifiedRed Hat ADP

      Show the original change
      Individual changes of this event as published by NVD
      TypeActionBeforeAfter
      Referenceadded
      —
      https://access.redhat.com/errata/RHSA-2026:58981

      Source identifier: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c

    2. Record modifiedRed Hat ADP

      1 individual change: Affected versions (publisher)

      Show the original change
      Individual changes of this event as published by NVD
      TypeActionBeforeAfter
      Affected versions (publisher)changed
      Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9 (+13)
      Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9 (+14)

      Source identifier: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c

    3. Record modifiedRed Hat ADP

      Show 2 original changes
      Individual changes of this event as published by NVD
      TypeActionBeforeAfter
      Referenceadded
      —
      https://access.redhat.com/errata/RHSA-2026:54769
      Affected versions (publisher)changed
      Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9 (+13)
      Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9 (+13)

      Source identifier: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c

    4. Record modifiedRed Hat ADP

      1 individual change: Affected versions (publisher)

      Show the original change
      Individual changes of this event as published by NVD
      TypeActionBeforeAfter
      Affected versions (publisher)changed
      Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9 (+13)
      Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9 (+13)

      Source identifier: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c

    5. Record modifiedRed Hat ADP

      Show 2 original changes
      Individual changes of this event as published by NVD
      TypeActionBeforeAfter
      Referenceadded
      —
      https://access.redhat.com/errata/RHSA-2026:53371
      Affected versions (publisher)changed
      Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9 (+12)
      Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9 (+13)

      Source identifier: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c

    6. Record modifiedRed Hat ADP

      1 individual change: Affected versions (publisher)

      Show the original change
      Individual changes of this event as published by NVD
      TypeActionBeforeAfter
      Affected versions (publisher)changed
      Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9 (+12)
      Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9 (+12)

      Source identifier: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c

    7. Record modifiedRed Hat ADP

      Show 2 original changes
      Individual changes of this event as published by NVD
      TypeActionBeforeAfter
      Referenceadded
      —
      https://access.redhat.com/errata/RHSA-2026:50205
      Affected versions (publisher)changed
      Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9 (+11)
      Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9 (+12)

      Source identifier: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c

    8. Record modifiedRed Hat ADP

      Show 2 original changes
      Individual changes of this event as published by NVD
      TypeActionBeforeAfter
      Referenceadded
      —
      https://access.redhat.com/errata/RHSA-2026:46836
      Affected versions (publisher)changed
      Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9 (+9)
      Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9 (+11)

      Source identifier: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c

    9. Record modifiedRed Hat ADP

      Show 2 original changes
      Individual changes of this event as published by NVD
      TypeActionBeforeAfter
      Referenceadded
      —
      https://access.redhat.com/errata/RHSA-2026:44481
      Affected versions (publisher)changed
      Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9 (+4)
      Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9 (+9)

      Source identifier: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c

    10. Record modifiedRed Hat ADP

      Show 4 original changes
      Individual changes of this event as published by NVD
      TypeActionBeforeAfter
      Referenceadded
      —
      https://access.redhat.com/errata/RHSA-2026:42736
      Referenceadded
      —
      https://access.redhat.com/errata/RHSA-2026:42739
      Referenceadded
      —
      https://access.redhat.com/errata/RHSA-2026:43420
      Affected versions (publisher)changed
      Red Hat Hardened Images, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 6 (+4)
      Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9 (+4)

      Source identifier: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c

    11. ReceivedVulnCheck

      CVSS V4.0: AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N

      CVSS V3.1: AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N

      Weakness type: CWE-59

      Description added or changed

      Show 9 original changes
      Individual changes of this event as published by NVD
      TypeActionBeforeAfter
      Affected versions (publisher)added
      —
      acl
      Tagadded
      —
      unsupported-when-assigned
      Descriptionadded
      —
      acl before version 2.4.0 contains a symlink traversal vulnerability in the libacl pathname-based functions acl_get_file(), acl_set_file(), acl_extended_file(), and acl_delete_def_file() that allows local attackers to escalate privileges by replacing any pathname component with a symbolic link. Attackers who control any component of a pathname processed by a privileged caller can redirect ACL read or write operations to arbitrary files or directories, enabling unauthorized manipulation of access control lists and local privilege escalation.
      CVSSadded
      —
      AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
      CVSSadded
      —
      AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
      Weakness type (CWE)added
      —
      CWE-59
      Referenceadded
      —
      https://cgit.git.savannah.nongnu.org/cgit/acl.git/commit/?id=24a227d0ab8576612194f8a56c2314389adc74a5
      Referenceadded
      —
      https://cgit.git.savannah.nongnu.org/cgit/acl.git/commit/?id=3589787cd589b34bdd9265936e17190b6d3f17d1
      Referenceadded
      —
      https://www.vulncheck.com/advisories/acl-symlink-traversal-privilege-escalation-via-libacl-functions

      Source identifier: disclosure@vulncheck.com

    One NVD translation into another language is hidden.

    Embed badge

    Show the severity and KEV status of this vulnerability on your site – with a link back here. The image is updated hourly.

    Badge preview for CVE-2026-54369
    <a href="https://intel.neosec.eu/en/cve/CVE-2026-54369"><img src="https://intel.neosec.eu/badge/cve/CVE-2026-54369.svg?lang=en" alt="CVE-2026-54369 – NEOSEC Intel" height="20"></a>