JerryScript 2.2.0 parser_emit_cbc_backward_branch assertion

CVSS Meta Temp Score
CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.
Current Exploit Price (≈)
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CTI Interest Score
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A vulnerability has been found in JerryScript 2.2.0 and classified as critical. The CWE definition for the vulnerability is CWE-617. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

There is an Assertion in '(flags >> CBC_STACK_ADJUST_SHIFT) >= CBC_STACK_ADJUST_BASE || (CBC_STACK_ADJUST_BASE - (flags >> CBC_STACK_ADJUST_SHIFT)) stack_depth' in parser_emit_cbc_backward_branch in JerryScript 2.2.0.

The weakness was released 06/11/2021. The advisory is shared for download at This vulnerability was named CVE-2020-23319 since 08/13/2020. The attack can only be initiated within the local network. A single authentication is required for exploitation. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 06/13/2021).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.



CPE 2.3infoedit

CPE 2.2infoedit


VulDB Meta Base Score: 5.5
VulDB Meta Temp Score: 5.5

VulDB Base Score: 5.5
VulDB Temp Score: 5.5
VulDB Vector: 🔒
VulDB Reliability: 🔍



VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍


Class: Unknown
CWE: CWE-617
ATT&CK: Unknown

Local: No
Remote: Partially

Availability: 🔒
Status: Not defined

Price Prediction: 🔍
Current Price Estimation: 🔒


Threat Intelligenceinfoedit

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍


Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒


08/13/2020 CVE assigned
06/11/2021 +302 days Advisory disclosed
06/11/2021 +0 days VulDB entry created
06/13/2021 +2 days VulDB last update


Status: Confirmed
Confirmation: 🔒

CVE: CVE-2020-23319 (🔒)


Created: 06/11/2021 01:34 PM
Updated: 06/13/2021 01:34 PM
Changes: (3) source_cve_assigned source_cve_nvd_summary advisory_confirm_url
Complete: 🔍


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