Arbitrary file disclosure via root-privileged symlink following
Published Dec 22, 2021 · Updated Aug 3, 2024
Local file inclusion in Lantronix PremierWave 2050 8.9.0.0R4 allows remote authenticated users to read arbitrary device files. Web Manager executes uploaded Python applications with reduced privileges, but Filesystem Browse follows attacker-created symlinks while retaining root privileges. Authorized access to both functions is required; successful exploitation exposes files such as /etc/shadow without altering them.
Summary
What happened
Local file inclusion in Lantronix PremierWave 2050 8.9.0.0R4 allows remote authenticated users to read arbitrary device files. Web Manager executes uploaded Python applications with reduced privileges, but Filesystem Browse follows attacker-created symlinks while retaining root privileges. Authorized access to both functions is required; successful exploitation exposes files such as /etc/shadow without altering them.
The record
- CVE
- CVE-2021-21878
- Published
- Dec 22, 2021
- Updated
- Aug 3, 2024
- Vendor
- Lantronix
- Product
- PremierWave 2050
- Classifications
- CWE-668, T1003.008
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Dec 22, 2021CVE publishedPublication date reported by the CVE source.
- Aug 3, 2024Record 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.
- Affected versionversion=Lantronix PremierWave 2050 8.9.0.0R4 (in QEMU)
What conditions does exploitation require?
What is affected?
Published CVSS scores
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.
Weakness, pattern, technique
Public exploit references
- Cisco Talos symlink file-disclosure demonstrationproof of concept · demonstrated
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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