CVE-2026-41898Network attack vector

Memory disclosure via unchecked callback-returned lengths

Published Apr 24, 2026 · Updated Apr 24, 2026

Buffer over-read in the openssl Rust crate 0.9.24 through 0.10.77 allows remote attackers to receive adjacent process memory during TLS exchanges. Its PSK and cookie-generation FFI trampolines trust a callback's returned usize and tell OpenSSL to serialize that many bytes without bounding it to the supplied slice. Applications expose memory only when an affected callback returns an oversized length and a remote peer initiates the corresponding TLS or DTLS exchange.

CVSS severity8.3
High
EPSS probability0.28%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Buffer over-read in the openssl Rust crate 0.9.24 through 0.10.77 allows remote attackers to receive adjacent process memory during TLS exchanges. Its PSK and cookie-generation FFI trampolines trust a callback's returned usize and tell OpenSSL to serialize that many bytes without bounding it to the supplied slice. Applications expose memory only when an affected callback returns an oversized length and a remote peer initiates the corresponding TLS or DTLS exchange.

The record

CVE
CVE-2026-41898
Published
Apr 24, 2026
Updated
Apr 24, 2026
Vendor
rust-openssl
Product
openssl
Classifications
CWE-126, CWE-130, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 24, 2026CVE publishedPublication date reported by the CVE source.
  2. Apr 24, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=>= 0.9.24, < 0.10.78

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

rust-openssl · opensslversion=>= 0.9.24, < 0.10.78

Published CVSS scores

5.3NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
8.3GitHub, Inc.CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:L/SC:N/SI:N/SA:N

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)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-126Buffer Over-read
CWE-130Improper Handling of Length Parameter Inconsistency
T1190Exploit Public-Facing Application

Public exploit references

No public exploit references are available in this record.

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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