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NVD / CVE Program· CNA openssl

CVE-2026-34181: PKCS#12 Files with PBMAC1 Are Accepted with Short HMAC Keys

Noroxi assessment

Priority: Monitor (action score 29/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 0.37% (FIRST EPSS).
  • Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. Special conditions such as timing or configuration are required.
  • Fixed version: OpenSSL OpenSSL 3.4.6, 3.5.7, 3.6.3; azl3 openvmm 0.2.0-1 on Azure Linux 3.0 Release Notes.
  • Mentioned 1 time in Turkish national cyber security advisories (siberguvenlik.gov.tr).

Low priority for now. Upgrade to OpenSSL OpenSSL 3.4.6, 3.5.7, 3.6.3; azl3 openvmm 0.2.0-1 on Azure Linux 3.0 Release Notes or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

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 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.

HighCVSS 7.4 · v3.1—No exploit Fix available
Published
Jun 9, 2026
Updated
Jul 23, 2026
EPSS
0.3% · 31th percentile

Report tools

JSON

Action score

29

Monitor

Low priority for now.

CVSS
29 / 40 · 7.4 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.3%

CISA SSVC decision

Exploitation
none
Automatable
no
Technical impact
partial

Vulnrichment: CISA's decision-tree inputs.

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • A fix has been released

If any of these changes, we'll tell you in the daily email digest.

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When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

VendorProduct
opensslopenssl

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Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • openssl openssl3.4.0 and later · before 3.4.6
  • openssl openssl3.5.0 and later · before 3.5.7
  • openssl openssl3.6.0 and later · before 3.6.3
  • openssl openssl4.0.0

Versions reported by the vendor

Affected version ranges reported by the assigning authority (openssl). Independent of NVD's CPE analysis and usually ahead of it.

  • OpenSSL OpenSSL

    • 4.0.0 and later · before 4.0.1affected · semver
    • 3.6.0 and later · before 3.6.3affected · semver
    • 3.5.0 and later · before 3.5.7affected · semver
    • 3.4.0 and later · before 3.4.6affected · semver

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
AlmaLinux:10opensslbefore 1:3.5.5-4.el10_2.alma.11:3.5.5-4.el10_2.alma.1
AlmaLinux:10openssl-develbefore 1:3.5.5-4.el10_2.alma.11:3.5.5-4.el10_2.alma.1
AlmaLinux:10openssl-libsbefore 1:3.5.5-4.el10_2.alma.11:3.5.5-4.el10_2.alma.1
AlmaLinux:10openssl-perlbefore 1:3.5.5-4.el10_2.alma.11:3.5.5-4.el10_2.alma.1
AlmaLinux:9opensslbefore 1:3.5.5-4.el9_81:3.5.5-4.el9_8
AlmaLinux:9openssl-develbefore 1:3.5.5-4.el9_81:3.5.5-4.el9_8
AlmaLinux:9openssl-libsbefore 1:3.5.5-4.el9_81:3.5.5-4.el9_8
AlmaLinux:9openssl-perlbefore 1:3.5.5-4.el9_81:3.5.5-4.el9_8
Alpine:v3.22opensslfrom 3.4.0 · before 3.5.7-r03.5.7-r0
Debian:13opensslbefore 3.5.6-1~deb13u23.5.6-1~deb13u2
Debian:14opensslbefore 3.6.3-13.6.3-1
openSUSE:Leap 16.0openssl-3before 3.5.0-160000.10.13.5.0-160000.10.1
openSUSE:Tumbleweedopenssl-3before 3.5.3-8.13.5.3-8.1
Red Hat:enterprise_linux:10.2opensslbefore 1:3.5.5-4.el10_21:3.5.5-4.el10_2
Red Hat:enterprise_linux:10.2openssl-debuginfobefore 1:3.5.5-4.el10_21:3.5.5-4.el10_2
Red Hat:enterprise_linux:10.2openssl-debugsourcebefore 1:3.5.5-4.el10_21:3.5.5-4.el10_2
Red Hat:enterprise_linux:10.2openssl-develbefore 1:3.5.5-4.el10_21:3.5.5-4.el10_2
Red Hat:enterprise_linux:10.2openssl-libsbefore 1:3.5.5-4.el10_21:3.5.5-4.el10_2
Red Hat:enterprise_linux:10.2openssl-libs-debuginfobefore 1:3.5.5-4.el10_21:3.5.5-4.el10_2
Red Hat:enterprise_linux:10.2openssl-perlbefore 1:3.5.5-4.el10_21:3.5.5-4.el10_2
Red Hat:enterprise_linux:9::appstreamopenssl-debuginfobefore 1:3.5.5-4.el9_81:3.5.5-4.el9_8
Red Hat:enterprise_linux:9::appstreamopenssl-debugsourcebefore 1:3.5.5-4.el9_81:3.5.5-4.el9_8
Red Hat:enterprise_linux:9::appstreamopenssl-develbefore 1:3.5.5-4.el9_81:3.5.5-4.el9_8
Red Hat:enterprise_linux:9::appstreamopenssl-libs-debuginfobefore 1:3.5.5-4.el9_81:3.5.5-4.el9_8

+78

Same product

openssl: all records

Other highest-scoring records for the same primary product.

  • CVE-2014-0160The (1) TLS and (2) DTLS implementations in OpenSSL 1.0.1 before 1.0.1g do not properly handle Heartbeat Extension packets, which allows remKEV
    90Now
  • CVE-2021-3711SM2 Decryption Buffer Overflow
    65This week
  • CVE-2003-0545Double free vulnerability in OpenSSL 0.9.7 allows remote attackers to cause a denial of service (crash) and possibly execute arbitrary code
    65This week

Published before and after this one in the same product

  • ← EarlierCVE-2026-31790Apr 7, 2026 · Incorrect Failure Handling in RSA KEM RSASVE Encapsulation
    30Monitor
  • ← EarlierCVE-2026-34180Jun 9, 2026 · Heap Buffer Over-read in ASN.1 Content Parsing
    30Monitor
  • Later →CVE-2026-34182Jun 9, 2026 · CMS AuthEnvelopedData Processing May Accept Forged Messages
    36Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
OpenSSL OpenSSL3.4.6Vendor (CNA)
OpenSSL OpenSSL3.5.7Vendor (CNA)
OpenSSL OpenSSL3.6.3Vendor (CNA)
OpenSSL OpenSSL4.0.1Vendor (CNA)
azl3 openvmm 0.2.0-1 on Azure Linux 3.0Release NotesMicrosoft (MSRC)
almalinux:openssl1:3.5.5-4.el10_2.alma.1 · AlmaLinux:10Package registry (OSV)
almalinux:openssl-devel1:3.5.5-4.el10_2.alma.1 · AlmaLinux:10Package registry (OSV)
almalinux:openssl-libs1:3.5.5-4.el10_2.alma.1 · AlmaLinux:10Package registry (OSV)
almalinux:openssl-perl1:3.5.5-4.el10_2.alma.1 · AlmaLinux:10Package registry (OSV)
alpine:openssl3.5.7-r0 · Alpine:v3.22Package registry (OSV)
debian:openssl3.5.6-1~deb13u2 · Debian:13Package registry (OSV)
opensuse:openssl-33.5.3-8.1 · openSUSE:TumbleweedPackage registry (OSV)
red hat:chunkah0:0.6.0-3.hum1 · Red Hat:hummingbird:1Package registry (OSV)
red hat:openssl1:3.5.5-4.el10_2 · Red Hat:enterprise_linux:10.2Package registry (OSV)
red hat:openssl-debuginfo1:3.5.5-4.el10_2 · Red Hat:enterprise_linux:10.2Package registry (OSV)
red hat:openssl-debugsource1:3.5.5-4.el10_2 · Red Hat:enterprise_linux:10.2Package registry (OSV)
red hat:openssl-devel1:3.5.5-4.el10_2 · Red Hat:enterprise_linux:10.2Package registry (OSV)
red hat:openssl-libs1:3.5.5-4.el10_2 · Red Hat:enterprise_linux:10.2Package registry (OSV)
red hat:openssl-libs-debuginfo1:3.5.5-4.el10_2 · Red Hat:enterprise_linux:10.2Package registry (OSV)
red hat:openssl-perl1:3.5.5-4.el10_2 · Red Hat:enterprise_linux:10.2Package registry (OSV)
red hat:openssl30:3.5.8-0.1.hum1 · Red Hat:hummingbird:1Package registry (OSV)
red hat:openssl3-devel0:3.5.8-0.1.hum1 · Red Hat:hummingbird:1Package registry (OSV)
red hat:python-cryptography0:50.0.0-1.hum1 · Red Hat:hummingbird:1Package registry (OSV)
red hat:python3-cryptography0:50.0.0-1.hum1 · Red Hat:hummingbird:1Package registry (OSV)
rocky linux:openssl1:3.5.5-4.el10_2 · Rocky Linux:10Package registry (OSV)
suse:openssl-33.5.0-160000.10.1 · SUSE:Linux Micro 6.2Package registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

No history yet (it accumulates with the daily EPSS job).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

  • CVE-2026-341820 days apartCMS AuthEnvelopedData Processing May Accept Forged Messages
    36Monitor
  • CVE-2026-7580377 days apartAEAD Forgeries with Empty Ciphertext When Using EVP_Cipher()
    36Monitor

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

National notice (Türkiye Cybersecurity Directorate / USOM)

Official security notices citing this record; remediation advice is on the agency's page.

All national notices →

Technical details

Attack conditions

  • Anyone who can reach it over the internet can trigger it.
  • No account or password is required.
  • No user action is required.
  • Special conditions such as timing or configuration are required.

If successful

Confidentiality
high · data can be read
Integrity
high · data or configuration can be modified
Availability
none
Attack vector
Network
Attack complexity
High
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality impact
High
Integrity impact
High
Availability impact
None

Weakness class (CWE)

CWE-354 · Improper Validation of Integrity Check Value

CVSS vector

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N

nvd-secondary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

ATT&CK techniques

—

Change log

  1. Fix✗ → ✓

For records you follow, these changes also arrive as notifications. →

References

Show all references (4 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records