CVE-2020-27540
Published: 26 January 2021
Summary
CVE-2020-27540 is a critical-severity Improper Verification of Cryptographic Signature (CWE-347) vulnerability in Company Cs-C2Shw Firmware. Its CVSS base score is 9.8 (Critical).
Operationally, ranked at the 42.3th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2020-20049
Vulnerability details
Bash injection vulnerability and bypass of signature verification in Rostelecom CS-C2SHW 5.0.082.1. The camera reads firmware update configuration from SD card file vc\version.json. fw-sign parameter and from this configuration is directly inserted into a bash command. Firmware update is run…
more
automatically if there is special file on the inserted SD card.
- CWE(s)
Related Threats
No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.
Affected Assets
Mitigating Controls
Likely Mitigating Controls AI
Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.
Requires verification of digital signatures using organization-approved certificates before installation, directly preventing improper verification of cryptographic signatures.
Component authenticity commonly depends on cryptographic signatures; the control enforces proper verification of those signatures.
PKI certificates under an approved policy require cryptographic signature verification on issuance and validation.
Requires cryptographic signatures on authoritative data and support for verifying the chain of trust.
Mandates verification of cryptographic signatures (e.g., DNSSEC RRSIG) on resolution responses, addressing missing or bypassed signature checks.
Integrity tools commonly rely on cryptographic signatures whose improper validation this weakness covers.
Authenticity validation commonly relies on cryptographic signature or certificate checks that this control enforces.