CVE-2026-78624

Executive Summary

CVE-2026-78624 is a path traversal vulnerability (CWE-22) in the Okta Access Gateway backup restore function. The restore routine fails to validate the filename embedded within an encrypted backup payload, allowing file contents to be written to unintended locations on the appliance filesystem. Successful exploitation requires high privileges (PR:H) and network access (AV:N), yielding a confidentiality-only impact (C:H/I:N/A:N) as scored at CVSS 4.9. Organizations running Okta Access Gateway with backup/restore administrative workflows exposed to privileged actors or compromised admin accounts are affected.

Technical Analysis

The vulnerability resides in the backup restore function of Okta Access Gateway. The root cause is insufficient validation of the filename embedded in an encrypted backup payload. When an operator initiates a restore operation, the appliance processes the archive contents and extracts files based on filenames contained within the payload. Because the application does not sanitize or constrain these embedded filenames, an attacker who can supply a crafted encrypted backup can cause file contents to be written to unintended locations on the appliance filesystem.

This is a classic path traversal (CWE-22) condition. The attack surface is the backup restore interface, which is administrative in nature — reflected in the CVSS vector PR:H (Privileges Required: High). The encrypted nature of the backup payload does not mitigate the flaw: the filename metadata within the payload is processed after or independent of cryptographic verification, allowing a privileged attacker with knowledge of the backup format to craft a malicious archive.

Per the CVSS vector, the impact is confidentiality-only (C:H). Integrity and availability are unaffected (I:N/A:N). This suggests the write-to-unintended-location primitive can be leveraged to overwrite or place files that expose sensitive content, rather than to corrupt the system or cause denial of service. The score of 4.9 is consistent with a medium-severity issue requiring privileged access and network reachability.

The exact filename field, archive format, and file paths involved are not disclosed in the available NVD description. No public PoC details, function names, or code paths are provided in the CVE data.

Exploitation Scenarios

No public PoC code was identified in the CVE data, though PoC status is listed as Public. The attack chain below is described at the vulnerability-class level, consistent with the sparse technical detail available.

1. Reconnaissance/target identification: An attacker with administrative access to an Okta Access Gateway appliance identifies the backup and restore functionality. Network exposure (AV:N) allows this from a remote management interface.

2. Triggering the flaw: The attacker constructs or modifies a backup payload in which the embedded filename contains path traversal sequences (e.g., directory traversal escaping the intended extraction directory). Because the restore function does not validate this embedded filename, the crafted value is honored during extraction.

3. Payload/execution method: The attacker uploads/restores the crafted encrypted backup through the administrative restore workflow. The appliance decrypts and processes the payload, writing file contents to a location determined by the unvalidated filename rather than a constrained target directory.

4. Post-exploitation impact: File contents are written to unintended locations. Per CVSS C:H/I:N/A:N, the primary consequence is exposure of confidential information. Depending on the destination path, this could overwrite or plant files that reveal sensitive data to the attacker. No integrity or availability impact is scored.

Note: The precise traversal target, filename field name, and cryptographic handling of the payload are not specified in available data and are not invented here.

Impact Assessment

Business impact centers on confidentiality loss of data on the Okta Access Gateway appliance. Because the vulnerable component is a backup restore function, the attacker is already in a privileged position (PR:H), limiting the population of viable attackers but increasing the severity of any successful action — privileged actors can place or overwrite files in security-relevant locations.

CVSS subscores: AV:N (network-exploitable), AC:L (no special conditions), PR:H (high privileges required), UI:N (no user interaction), S:U (impact scoped to the appliance), C:H (high confidentiality impact), I:N (no integrity impact), A:N (no availability impact). Blast radius is generally limited to the Access Gateway appliance itself (S:U), but data exposed could include backup contents or configuration material with downstream relevance to federated identity operations.

EPSS is 0.00352 (28.9th percentile), indicating low predicted exploitation likelihood in the near term. CISA KEV: NO — no confirmed in-the-wild exploitation. No affected version range, OSV package data, or threat actor campaign was provided.

Detection Guidance

Sigma Rule

title: Okta Access Gateway Backup Restore Path Traversal Attempt
id: 8f3c1a2e-7b4d-4c9a-9e21-0d5a6b7c8d90
status: experimental
description: Detects path traversal sequences in backup restore operations targeting Okta Access Gateway
references:
  - https://nvd.nist.gov/vuln/detail/CVE-2026-78624
author: Valters IT Threat Intelligence
date: 2026/01/01
logsource:
  category: webserver
  product: okta_access_gateway
detection:
  selection_method:
    cs-method:
      - 'POST'
      - 'PUT'
  selection_uri:
    cs-uri-stem|contains:
      - 'restore'
      - 'backup'
  selection_traversal:
    cs-uri-query|contains:
      - '../'
      - '..\\'
      - '%2e%2e%2f'
      - '%2e%2e%5c'
  condition: selection_method and selection_uri and selection_traversal
falsepositives:
  - Legitimate backup filenames containing unusual characters
level: medium
tags:
  - attack.t1505
  - cve.2026.78624

YARA Rule

rule CVE_2026_78624_Okta_Backup_PathTraversal
{
    meta:
        description = "Detects crafted Okta Access Gateway backup payloads containing path traversal filenames"
        author = "Valters IT Threat Intelligence"
        reference = "https://nvd.nist.gov/vuln/detail/CVE-2026-78624"
        date = "2026-01-01"
        cve = "CVE-2026-78624"

    strings:
        $traversal1 = "../../"
        $traversal2 = "..\\..\\"
        $traversal3 = "%2e%2e%2f"
        $traversal4 = "%2e%2e%5c"
        $bak1 = "backup" nocase
        $bak2 = "restore" nocase

    condition:
        (any of ($traversal*)) and (any of ($bak*))
}

Suricata IDS Rule

alert http any any -> any any (msg:"CVE-2026-78624 Okta Access Gateway Backup Restore Path Traversal Attempt"; flow:established,to_server; http.method; content:"POST"; http.uri; content:"restore"; nocase; http.uri; content:"../"; nocase; reference:cve,2026-78624; reference:url,nvd.nist.gov/vuln/detail/CVE-2026-78624; classtype:attempted-admin; sid:202678624; rev:1;)

Elastic Detection

network where
  http.request.method in ("POST", "PUT") and
  stringContains(http.request.uri, "restore") and
  (stringContains(http.request.uri, "../") or
   stringContains(http.request.uri, "..%2f") or
   stringContains(http.request.uri, "..\\"))

Splunk SPL Query

index=web sourcetype=okta_access_gateway
| search (method=POST OR method=PUT) uri_path IN ("*restore*", "*backup*")
| eval traversal=if(match(uri_query, "(\.\./|\.\.\\|%2e%2e%2f|%2e%2e%5c)"), "suspected", "clean")
| where traversal="suspected"
| stats count min(_time) as first_seen max(_time) as last_seen by src_ip, uri_path, uri_query
| sort - count

Wazuh OSSEC Rule

<group name="okta,access_gateway,web,">
  <rule id="100724" level="10">
    <decoded_as>web-accesslog</decoded_as>
    <url>restore|backup</url>
    <match>\.\./|\.\.\\|%2e%2e%2f|%2e%2e%5c</match>
    <description>CVE-2026-78624: Okta Access Gateway backup restore path traversal attempt detected</description>
    <mitre>
      <id>T1505</id>
    </mitre>
    <group>cve_2026_78624,</group>
  </rule>
</group>

Mitigation & Patch Guidance

Patch confidence is 2/4 (CLAIMED — a single source via NVD claims a patch exists, but this has not been independently confirmed). Treat remediation as unverified until validated against a vendor-published advisory and version.

1. Immediate mitigations: Restrict access to the backup/restore administrative interface to trusted networks and privileged operators only. Enforce least privilege and strong authentication for any account capable of initiating a restore. Audit existing backup payloads for embedded path traversal sequences before restore operations. Disable or tightly gate the restore function if not operationally required. Monitor for traversal patterns in restore requests using the detection rules above.

2. Patch/upgrade steps: Consult the Okta Access Gateway vendor advisory to obtain the confirmed fixed version and apply it. Because patch confidence is only CLAIMED, verify the fix by reviewing release notes and confirming the version string. Do not rely on the NVD reference alone — confirm through Okta's official security advisories before closing the vulnerability.

3. Long-term hardening: Implement input validation that constrains embedded filenames during archive extraction (canonicalize paths and enforce confinement to an intended directory). Adopt secure archive-extraction coding practices. Maintain an inventory of appliances and their firmware/software versions. Monitor EPSS and CISA KEV for changes indicating active exploitation.

References

• NVD — CVE-2026-78624: https://nvd.nist.gov/vuln/detail/CVE-2026-78624
• MITRE CWE-22 — Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal'): https://cwe.mitre.org/data/definitions/22.html
• MITRE ATT&CK T1505 — Server Software Component: https://attack.mitre.org/techniques/T1505/
• Okta Security Advisories (vendor advisory portal): https://trust.okta.com/security-advisories/
• FIRST EPSS — CVE-2026-78624 scoring: https://api.first.org/data/v1/epss?cve=CVE-2026-78624

No named threat actor campaigns or confirmed exploit-in-the-wild evidence were identified for CVE-2026-78624 at the time of writing. CISA KEV status is NO. PoC status is listed as Public, but no exploit code was provided in the source data.