CVE-2021-26906 Details
A vulnerability was found in Digium Asterisk up to 13.38.1/16.16.0/17.9.1/18.2.0 (Communications System). It has been declared as problematic. This vulnerability affects an unknown function of the file res_pjsip_session.c of the component SDP Negotiation. Upgrading to version 13.38.2, 16.16.1, 17.9.2 or 18.2.1 eliminates this vulnerability. The upgrade is hosted for download at downloads.asterisk.org.
View at NVD
Exploit prediction scoring system (EPSS) score for CVE-2021-26906
EPSS (Exploit Prediction Scoring System): EPSS predicts the likelihood that a vulnerability will be exploited in the wild. A higher percentage means a greater chance of an exploit occurring. The EPSS model produces a probability score between 0 and 1 (0 and 100%).
0.51 Probability of exploitation activity being observed over the next 30 days (66th percentile)
CVSS score for CVE-2021-26906
CVSS (Common Vulnerability Scoring System): An open framework owned and managed by FIRST.Org, Inc. that assigns a numerical score from 0 to 10 to software vulnerabilities to indicate their severity.
5.9 Medium
Products affected by CVE-2021-26906
Asterisk 13.11.2
Asterisk 13.12.0
Asterisk 13.12.1
Asterisk 13.12.2
Asterisk 13.13.0
DVE Score by Bitsight AI
DVE scores complement traditional static scoring systems like CVSS with Bitsight AI powered real-time threat intelligence and underground cyber criminal activity so that security teams can reduce alert fatigue and focus on vulnerabilities most likely to be exploited.
Not available
More on DVE scores

CVE-2021-26906 Global Footprint

Top 10 Identified Countries

Country Observations Percentage
US 2,980 28.07%
BR 708 6.67%
DE 519 4.89%
MX 447 4.21%
IN 422 3.98%
RU 328 3.09%
CA 323 3.04%
IT 257 2.42%
GB 244 2.30%
BD 224 2.11%

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CVE-2021-26906 Industry Footprint

Top 10 Identified Industries

*Service provider organizations (typically Technology and Telecommunications) are disproportionally represented in the results given their upstream ownership of end-user infrastructure. See our FAQs.

Industry* Observations Percentage
Telecommunications 2,702 48.61%
Technology 2,687 48.34%
Business Services 31 0.56%
Manufacturing 21 0.38%
Education 21 0.38%
Utilities 20 0.36%
Tourism/Hospitality 14 0.25%
Government/Politics 12 0.22%
Consumer Goods 9 0.16%
Aerospace/Defense 7 0.13%

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