Security Resilience

CVE-2026-34181

Openssl 3.4.0 – 3.4.6

Published
09 June 2026
Modified
17 June 2026
Patch / advisory
CVSS Score v3.1 7.4
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
EPSS Score 0.0018 7th percentile
Risk Priority 54 floored blend · peak EPSS

CVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.

Summary

CVE-2026-34181 is a high-severity Improper Validation of Integrity Check Value (CWE-354) vulnerability in Openssl Openssl. Its CVSS base score is 7.4 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique OS Credential Dumping (T1003); ranked at the 7th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to SC-13 (Cryptographic Protection) and SC-8 (Transmission Confidentiality and Integrity) — see the control section below for these in your framework.

EU & UK References

Vulnerability Data

Issue Summary: The PKCS#12 file processing fails to perform sufficient input validation for files that use Password-Based Message Authentication Code 1 (PBMAC1) integrity mechanism allowing a certificate and private key forgery. Impact Summary: An attacker impersonating a user can cause…

more

a service reading PKCS#12 files to accept forged certificates and private keys with a 1 in 256 probability. If a service accepting PKCS#12 files is using passwords for authenticating the received files, the attacker can create unencrypted PKCS#12 files that use PBMAC1 authentication that specifies an HMAC key of only one byte, allowing them to craft a file that will be accepted with a 1 in 256 probability. That would then cause the service to accept a certificate and private key controlled by the attacker. The FIPS modules are not affected by this issue, as the affected code is outside the OpenSSL FIPS module boundary.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1003 OS Credential Dumping Credential Access
Adversaries may attempt to dump credentials to obtain account login and credential material, normally in the form of a hash or a clear text password.
T1010 Application Window Discovery Discovery
Adversaries may attempt to get a listing of open application windows.
T1016.002 Wi-Fi Discovery Discovery
Adversaries may search for information about Wi-Fi networks, such as network names and passwords, on compromised systems.
T1021 Remote Services Lateral Movement
Adversaries may use [Valid Accounts](https://attack.
T1021.004 SSH Lateral Movement
Adversaries may use [Valid Accounts](https://attack.
T1021.005 VNC Lateral Movement
Adversaries may use [Valid Accounts](https://attack.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2026-75803Same product: Openssl Openssl
CVE-2026-34182Same product: Openssl Openssl
CVE-2025-11187Same product: Openssl Openssl
CVE-2026-45447Same product: Openssl Openssl
CVE-2025-15467Same product: Openssl Openssl
CVE-2023-3446Same product: Openssl Openssl
CVE-2023-6129Same product: Openssl Openssl
CVE-2026-28387Same product: Openssl Openssl
CVE-2016-6309Same product: Openssl Openssl
CVE-2026-84783Same product: Openssl Openssl

Affected Assets

openssl
openssl
4.0.0 · 3.4.0 — 3.4.6 · 3.5.0 — 3.5.7 · 3.6.0 — 3.6.3

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)
  • 10 hardening rules · 4 OS baselines
Validate
Prove the fix (OWASP ASVS)
  • V10.4.12

Mitigating Controls (NIST 800-53 r5) AI

Requires integrity verification tools that detect unauthorized changes when checksum validation is missing or flawed.

Mandates cryptographic mechanisms that include integrity protection, preventing improper checksum validation.

Requires protection of transmitted information integrity, directly mandating correct validation of integrity checks.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

ID.RA-09 partial match
blocks

Mandates pre-acquisition integrity assessment, addressing only the initial portion of the weakness lifecycle.

PR.DS-01 partial match
blocks

Requires cryptographic hashes and signatures that directly enforce integrity-check validation for data at rest.

PR.DS-02 partial match
blocks

Requires cryptographic hashes and signatures that directly enforce integrity-check validation for data in transit.

RC.RP-03 partial match
blocks

Requires verification of backup integrity, covering validation only within recovery scenarios.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

removes
removes
removes
removes
removes

Hardening callouts derived

Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (higher-evidence rows only; rows rated `none` are excluded).

Oracle Linux 8 (2 rules)
  • V-248574 YUM must be configured to prevent the installation of patches, service packs, device drivers, or OL 8 system components that have not been digitally signed using a certificate that is recognized and approved by the organization. blocks CWE-354
  • V-248575 OL 8 must prevent the installation of software, patches, service packs, device drivers, or operating system components of local packages without verification they have been digitally signed using a certificate that is issued by a Certificate Authority (CA) that is recognized and approved by the organization. blocks CWE-354
Oracle Linux 9 (1 rule)
  • V-271523 OL 9 must check the GPG signature of locally installed software packages before installation. blocks CWE-354
RHEL 7 (2 rules)
  • V-204447 The Red Hat Enterprise Linux operating system must prevent the installation of software, patches, service packs, device drivers, or operating system components from a repository without verification they have been digitally signed using a certificate that is issued by a Certificate Authority (CA) that is recognized and approved by the organization. blocks CWE-354
  • V-204448 The Red Hat Enterprise Linux operating system must prevent the installation of software, patches, service packs, device drivers, or operating system components of local packages without verification they have been digitally signed using a certificate that is issued by a Certificate Authority (CA) that is recognized and approved by the organization. blocks CWE-354
RHEL 8 (2 rules)
  • V-230264 RHEL 8 must prevent the installation of software, patches, service packs, device drivers, or operating system components from a repository without verification they have been digitally signed using a certificate that is issued by a Certificate Authority (CA) that is recognized and approved by the organization. blocks CWE-354
  • V-230265 RHEL 8 must prevent the installation of software, patches, service packs, device drivers, or operating system components of local packages without verification they have been digitally signed using a certificate that is issued by a Certificate Authority (CA) that is recognized and approved by the organization. blocks CWE-354

References