CVE-2026-101283: CWE-122 Heap-based buffer overflow in esnet iperf3
A critical heap-based buffer overflow vulnerability exists in esnet iperf3 versions 3.20 and 3.21 in the decrypt_rsa_message() function. The flaw allows an unauthenticated client to overflow a 256-byte RSA buffer by providing an oversized authtoken, potentially leading to memory corruption. This vulnerability is fixed in version 3.22.
AI Analysis
Technical Summary
CVE-2026-101283 is a heap-based buffer overflow vulnerability in esnet iperf3 versions 3.20 and 3.21. The issue occurs in the decrypt_rsa_message() function where a 256-byte RSA buffer is read using BIO_read with an attacker-controlled ciphertext length. Although a guard warning exists, it does not prevent an unauthenticated client from overflowing the heap by sending an oversized authtoken. This vulnerability has a CVSS 4.0 score of 9.2, indicating critical severity, and was fixed in version 3.22.
Potential Impact
An unauthenticated attacker can exploit this vulnerability to overflow the heap memory of the iperf3 process, potentially causing memory corruption, application crashes, or arbitrary code execution. The high CVSS score reflects the network attack vector, low attack complexity, and high impact on confidentiality, integrity, and availability.
Mitigation Recommendations
Upgrade iperf3 to version 3.22 or later, where this heap-based buffer overflow vulnerability is fixed. No other mitigations are specified or recommended.
CVE-2026-101283: CWE-122 Heap-based buffer overflow in esnet iperf3
Description
A critical heap-based buffer overflow vulnerability exists in esnet iperf3 versions 3.20 and 3.21 in the decrypt_rsa_message() function. The flaw allows an unauthenticated client to overflow a 256-byte RSA buffer by providing an oversized authtoken, potentially leading to memory corruption. This vulnerability is fixed in version 3.22.
CVSS v4.0
Score 9.2critical
Affected software
esnet
iperf3
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-101283 is a heap-based buffer overflow vulnerability in esnet iperf3 versions 3.20 and 3.21. The issue occurs in the decrypt_rsa_message() function where a 256-byte RSA buffer is read using BIO_read with an attacker-controlled ciphertext length. Although a guard warning exists, it does not prevent an unauthenticated client from overflowing the heap by sending an oversized authtoken. This vulnerability has a CVSS 4.0 score of 9.2, indicating critical severity, and was fixed in version 3.22.
Potential Impact
An unauthenticated attacker can exploit this vulnerability to overflow the heap memory of the iperf3 process, potentially causing memory corruption, application crashes, or arbitrary code execution. The high CVSS score reflects the network attack vector, low attack complexity, and high impact on confidentiality, integrity, and availability.
Mitigation Recommendations
Upgrade iperf3 to version 3.22 or later, where this heap-based buffer overflow vulnerability is fixed. No other mitigations are specified or recommended.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- Anthropic
- Date Reserved
- 2026-09-28T12:01:09.970Z
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 6abd83bd2a4e24523da50866
Added to database: 09/30/2026, 21:48:45 UTC
Last enriched: 09/30/2026, 22:02:58 UTC
Last updated: 09/30/2026, 22:12:14 UTC
Views: 6
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