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TI-2026-30193 Aliases CVE-2026-41676GHSA-pqf5-4pqq-29f5

rust-openssl: Deriver::derive and PkeyCtxRef::derive can overflow short buffers on OpenSSL 1.1.1

Priority LOW 39CWE-131Published · Updated

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
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA and GitHub. Impact type from CWE-131 and the CVSS impact.

Summary

rust-openssl provides OpenSSL bindings for the Rust programming language. From 0.9.27 to before 0.10.78, Deriver::derive (and PkeyCtxRef::derive) sets len = buf.len() and passes it as the in/out length to EVP_PKEY_derive, relying on OpenSSL to honor it. On OpenSSL 1.1.x, X25519, X448, DH and HKDF-extract ignore the incoming *keylen, unconditionally writing the full shared secret (32/56/prime-size bytes). A caller passing a short slice gets a heap/stack overflow from safe code. OpenSSL 3.x providers do check, so this only impacts older OpenSSL. This vulnerability is fixed in 0.10.78.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00285 21st percentileScored 2026-11-07
Fix Fixed rust-openssl (rust-openssl): 0.10.78openssl (crates.io): 0.10.78

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
rust-opensslrust-openssl0.9.27 to before 0.10.780.10.78Patch availableCNA
—openssl (crates.io)0.9.27 to before 0.10.780.10.78Patch availableGHSA-pqf5-4pqq-29f5
  • rust-openssl Vendorrust-openssl Affected 0.9.27 to before 0.10.78 Fixed in 0.10.78 Patch available CNA
  • openssl (crates.io) Vendor— Affected 0.9.27 to before 0.10.78 Fixed in 0.10.78 Patch available GHSA-pqf5-4pqq-29f5

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:rust-openssl_project:rust-openssl:*:*:*:*:*:rust:*:*0.9.27 to before 0.10.78Vulnerablerust-openssl
  • cpe:2.3:a:rust-openssl_project:rust-openssl:*:*:*:*:*:rust:*:* Versions 0.9.27 to before 0.10.78 Vulnerable ·rust-openssl

Remediation

  • Fix · CNA rust-openssl (rust-openssl) Fixed in 0.10.78
  • Fix · GHSA-pqf5-4pqq-29f5 openssl (crates.io) Fixed in 0.10.78 Advisory →

Vendor assessments

Red Hat

Red Hat's page for this CVE →

Not affected: 1 product
  • Red Hat

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-41676
  2. 2026-10-03 Alias added: GHSA-pqf5-4pqq-29f5

References

Advisory 2

Other 4

  • TI-2018-14959 An issue was discovered in the openssl crate before 0.10.9 for Rust. CVSS 3.0CRITICAL 9.8
  • TI-2026-30198 rust-openssl: MdCtxRef::digest_final() writes past caller buffer with no length check CVSS 4.0HIGH 8.1
  • TI-2016-08969 An issue was discovered in the openssl crate before 0.9.0 for Rust. CVSS 3.0HIGH 8.1
  • TI-2026-30300 rust-openssl: Unchecked callback-returned length in PSK and cookie generate trampolines… CVSS 4.0HIGH 8.3
  • TI-2026-30195 rust-openssl: Incorrect bounds assertion in aes key wrap CVSS 4.0HIGH 7.2
  • TI-2026-30194 rust-openssl: Out-of-bounds read in PEM password callback when user callback returns an oversized length CVSS 4.0LOW 1.7

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences