CVE-2020-27540Public exploit

Physical command execution via unescaped update signature

Published Jan 25, 2021 · Updated Aug 4, 2024

Command injection in Rostelecom CS-C2SHW 5.0.082.1 allows physically proximate attackers to execute Bash commands via an SD card. The updater reads fw-sign from vc\version.json and inserts it directly into a Bash command without escaping while bypassing signature verification. A prepared card containing the special update trigger must be inserted, after which the camera starts the firmware update automatically.

CVSS severity9.8
Critical
EPSS probability0.83%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Command injection in Rostelecom CS-C2SHW 5.0.082.1 allows physically proximate attackers to execute Bash commands via an SD card. The updater reads fw-sign from vc\version.json and inserts it directly into a Bash command without escaping while bypassing signature verification. A prepared card containing the special update trigger must be inserted, after which the camera starts the firmware update automatically.

The record

CVE
CVE-2020-27540
Published
Jan 25, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-347, T1200, T1059.004
Attack vector
physical
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jan 25, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 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?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectorphysical
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

7.5NIST NVDAV:N/AC:L/Au:N/C:P/I:P/A:P
9.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

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)
Vectorphysical
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-347Improper Verification of Cryptographic Signature
T1200Hardware Additions
T1059.004Unix Shell

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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