Heap-based buffer overflow in esnet iperf3
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Attack requirements
- Present
- Impact type
- Code execution
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- No fix listed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-122 and the CVSS impact.
Summary
iperf3 3.20–3.21 (esnet/iperf) has a pre-auth heap buffer overflow in decrypt_rsa_message(): a 256-byte RSA buffer is BIO_read with the attacker-controlled ciphertext length (guard warns only), so an unauthenticated client overflows the heap via an oversized authtoken; fixed in 3.22
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Total
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
Remediation
No fixed version listed by the sources yet.
Timeline
- 2026-10-02 Threatist record created from CVE-2026-101283
- 2026-10-03 Alias added: GHSA-pwcx-5qh6-2pxc
References
More esnet vulnerabilities
- TI-2026-65296 iperf3 < 3.22 UDP Receive Worker Infinite Loop DoS CVSS 4.0HIGH 8.7
- TI-2026-65170 Use after free in esnet iperf3 CVSS 4.0CRITICAL 9.2
Sources
- CVE-2026-101283 · CVE Program
- CVE-2026-101283 · NVD
- FIRST EPSS
- GHSA-pwcx-5qh6-2pxc · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences