CVE-2021-39283Public exploit

Application exit via repeated RTSP command sequence

Published Aug 18, 2021 · Updated Aug 4, 2024

Reachable assertion in Live555 through 1.08 allows attackers to terminate an application via repeated RTSP SETUP and PLAY commands. FramedSource.cpp processes the repeated command sequence until a state assertion fails instead of rejecting the invalid transition. The consequence is limited to application exit; published records do not establish data disclosure, modification, or a reliable network-position gate.

CVSS severity5.5
Medium
EPSS probability0.86%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Reachable assertion in Live555 through 1.08 allows attackers to terminate an application via repeated RTSP SETUP and PLAY commands. FramedSource.cpp processes the repeated command sequence until a state assertion fails instead of rejecting the invalid transition. The consequence is limited to application exit; published records do not establish data disclosure, modification, or a reliable network-position gate.

The record

CVE
CVE-2021-39283
Published
Aug 18, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-617, T1499.004
Attack vector
Unavailable
Privileges
Unavailable

Timeline

How it unfolded

  1. Aug 18, 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 vectorUnavailable in this record.
Required privilegesUnavailable in this record.

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

5.5NIST National Vulnerability DatabaseCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
4.3NIST National Vulnerability DatabaseAV:N/AC:M/Au:N/C:N/I:N/A:P

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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
VectorUnavailable
PrivilegesUnavailable
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-617Reachable Assertion
T1499.004Application or System Exploitation

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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