CVE-2023-37206Public exploitNetwork attack vector

Local file disclosure via followed upload symlinks

Published Jul 5, 2023 · Updated Feb 13, 2025

Improper symlink handling in Mozilla Firefox before 115 allows remote attackers to read local files through a user-approved directory upload. GetFilesHelper recursively enumerates symlinks, and File/Blob streams open their targets without O_NOFOLLOW, sending target contents as selected files. Exploitation requires a user on Linux or macOS to extract an attacker-supplied archive and upload its booby-trapped directory to a malicious website.

CVSS severity6.5
Medium
EPSS probability0.71%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper symlink handling in Mozilla Firefox before 115 allows remote attackers to read local files through a user-approved directory upload. GetFilesHelper recursively enumerates symlinks, and File/Blob streams open their targets without O_NOFOLLOW, sending target contents as selected files. Exploitation requires a user on Linux or macOS to extract an attacker-supplied archive and upload its booby-trapped directory to a malicious website.

The record

CVE
CVE-2023-37206
Published
Jul 5, 2023
Updated
Feb 13, 2025
Vendor
Mozilla
Product
Firefox
Classifications
CWE-59
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jul 5, 2023CVE publishedPublication date reported by the CVE source.
  2. Feb 13, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=unspecified <115

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Mozilla · Firefoxversion=unspecified <115

Published CVSS scores

6.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

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

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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