Critical severity · published Sep 30, 2026
CVE-2026-101283
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…
9.2
CVSS
0.4%
EPSS
No
On KEV
Description
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
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 32% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
IP
iperf3 · esnet
3.20; 3.21 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-101283
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-101283
newreleases.io
https://newreleases.io/project/github/esnet/iperf/release/3.22
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