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NVD / CVE Program· CNA openssl

CVE-2026-22796: ASN1_TYPE Type Confusion in the PKCS7_digest_from_attributes() function

Noroxi assessment

Priority: Monitor (action score 21/100)

  • 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: 0.58% (FIRST EPSS).
  • Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
  • According to CISA the attack is automatable: targets can be found by mass scanning.
  • Fixed version: OpenSSL OpenSSL 3.0.19, 3.3.6, 3.4.4; azl3 openvmm 0.2.0-1 on Azure Linux 3.0 Release Notes.

Low priority for now. Upgrade to OpenSSL OpenSSL 3.0.19, 3.3.6, 3.4.4; 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: A type confusion vulnerability exists in the signature verification of signed PKCS#7 data where an ASN1_TYPE union member is accessed without first validating the type, causing an invalid or NULL pointer dereference when processing malformed PKCS#7 data. Impact summary: An application performing signature verification of PKCS#7 data or calling directly the PKCS7_digest_from_attributes() function can be caused to dereference an invalid or NULL pointer when reading, resulting in a Denial of Service. The function PKCS7_digest_from_attributes() accesses the message digest attribute value without validating its type. When the type is not V_ASN1_OCTET_STRING, this results in accessing invalid memory through the ASN1_TYPE union, causing a crash. Exploiting this vulnerability requires an attacker to provide a malformed signed PKCS#7 to an application that verifies it. The impact of the exploit is just a Denial of Service, the PKCS7 API is legacy and applications should be using the CMS API instead. For these reasons the issue was assessed as Low severity. The FIPS modules in 3.5, 3.4, 3.3 and 3.0 are not affected by this issue, as the PKCS#7 parsing implementation is outside the OpenSSL FIPS module boundary. OpenSSL 3.6, 3.5, 3.4, 3.3, 3.0, 1.1.1 and 1.0.2 are vulnerable to this issue.

MediumCVSS 5.3 · v3.1—No exploit Fix available
Published
Jan 27, 2026
Updated
Oct 15, 2026
EPSS
0.5% · 48th percentile

Report tools

JSON

Action score

21

Monitor

Low priority for now.

CVSS
21 / 40 · 5.3 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.5%

CISA SSVC decision

Exploitation
none
Automatable
yes
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

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  • 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 openssl1.0.2 and later · before 1.0.2zn
  • openssl openssl1.1.1 and later · before 1.1.1ze
  • openssl openssl3.0.0 and later · before 3.0.19
  • openssl openssl3.3.0 and later · before 3.3.6
  • openssl openssl3.4.0 and later · before 3.4.4
  • openssl openssl3.5.0 and later · before 3.5.5
  • openssl openssl3.6.0 and later · before 3.6.1

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

    • 3.6.0 and later · before 3.6.1affected · semver
    • 3.5.0 and later · before 3.5.5affected · semver
    • 3.4.0 and later · before 3.4.4affected · semver
    • 3.3.0 and later · before 3.3.6affected · semver
    • 3.0.0 and later · before 3.0.19affected · semver
    • 1.1.1 and later · before 1.1.1zeaffected
    • 1.0.2 and later · before 1.0.2znaffected

Package-level exposure

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

EcosystemPackageAffected rangeFix
AlmaLinux:10opensslbefore 1:3.5.1-7.el10_1.alma.11:3.5.1-7.el10_1.alma.1
AlmaLinux:10openssl-develbefore 1:3.5.1-7.el10_1.alma.11:3.5.1-7.el10_1.alma.1
AlmaLinux:10openssl-libsbefore 1:3.5.1-7.el10_1.alma.11:3.5.1-7.el10_1.alma.1
AlmaLinux:10openssl-perlbefore 1:3.5.1-7.el10_1.alma.11:3.5.1-7.el10_1.alma.1
AlmaLinux:9opensslbefore 1:3.5.1-7.el9_71:3.5.1-7.el9_7
AlmaLinux:9openssl-develbefore 1:3.5.1-7.el9_71:3.5.1-7.el9_7
AlmaLinux:9openssl-libsbefore 1:3.5.1-7.el9_71:3.5.1-7.el9_7
AlmaLinux:9openssl-perlbefore 1:3.5.1-7.el9_71:3.5.1-7.el9_7
Alpine:v3.17opensslfrom 1.0.2 · before 3.0.19-r03.0.19-r0
Alpine:v3.20opensslfrom 1.0.2 · before 3.3.6-r03.3.6-r0
Alpine:v3.22opensslfrom 1.0.2 · before 3.5.5-r03.5.5-r0
Debian:11opensslbefore 1.1.1w-0+deb11u51.1.1w-0+deb11u5
Debian:12opensslbefore 3.0.18-1~deb12u23.0.18-1~deb12u2
Debian:13opensslbefore 3.5.4-1~deb13u23.5.4-1~deb13u2
Debian:14opensslbefore 3.5.5-13.5.5-1
openSUSE:Leap 15.6openssl-1_0_0before 1.0.2p-150000.3.102.11.0.2p-150000.3.102.1
openSUSE:Leap 15.6openssl-1_1before 1.1.1w-150600.5.21.11.1.1w-150600.5.21.1
openSUSE:Leap 15.6openssl-3before 3.1.4-150600.5.42.13.1.4-150600.5.42.1
openSUSE:Leap 16.0openssl-3before 3.5.0-160000.5.13.5.0-160000.5.1
Red Hat:enterprise_linux:10.1opensslbefore 1:3.5.1-7.el10_11:3.5.1-7.el10_1
Red Hat:enterprise_linux:10.1openssl-debuginfobefore 1:3.5.1-7.el10_11:3.5.1-7.el10_1
Red Hat:enterprise_linux:10.1openssl-debugsourcebefore 1:3.5.1-7.el10_11:3.5.1-7.el10_1
Red Hat:enterprise_linux:10.1openssl-develbefore 1:3.5.1-7.el10_11:3.5.1-7.el10_1
Red Hat:enterprise_linux:10.1openssl-libsbefore 1:3.5.1-7.el10_11:3.5.1-7.el10_1

+33

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-2025-69421Jan 27, 2026 · NULL Pointer Dereference in PKCS12_item_decrypt_d2i_ex function
    30Monitor
  • ← EarlierCVE-2026-22795Jan 27, 2026 · Missing ASN1_TYPE validation in PKCS#12 parsing
    22Monitor
  • Later →CVE-2025-15467Jan 27, 2026 · Stack buffer overflow in CMS (Auth)EnvelopedData parsing
    57Plan

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 OpenSSL3.0.19Vendor (CNA)
OpenSSL OpenSSL3.3.6Vendor (CNA)
OpenSSL OpenSSL3.4.4Vendor (CNA)
OpenSSL OpenSSL3.5.5Vendor (CNA)
OpenSSL OpenSSL3.6.1Vendor (CNA)
azl3 openvmm 0.2.0-1 on Azure Linux 3.0Release NotesMicrosoft (MSRC)
almalinux:openssl1:3.5.1-7.el10_1.alma.1 · AlmaLinux:10Package registry (OSV)
almalinux:openssl-devel1:3.5.1-7.el10_1.alma.1 · AlmaLinux:10Package registry (OSV)
almalinux:openssl-libs1:3.5.1-7.el10_1.alma.1 · AlmaLinux:10Package registry (OSV)
almalinux:openssl-perl1:3.5.1-7.el10_1.alma.1 · AlmaLinux:10Package registry (OSV)
alpine:openssl3.0.19-r0 · Alpine:v3.17Package registry (OSV)
debian:openssl3.0.18-1~deb12u2 · Debian:12Package registry (OSV)
opensuse:openssl-1_0_01.0.2p-150000.3.102.1 · openSUSE:Leap 15.6Package registry (OSV)
opensuse:openssl-1_11.1.1w-150600.5.21.1 · openSUSE:Leap 15.6Package registry (OSV)
opensuse:openssl-33.1.4-150600.5.42.1 · openSUSE:Leap 15.6Package registry (OSV)
red hat:openssl1:3.5.1-7.el10_1 · Red Hat:enterprise_linux:10.1Package registry (OSV)
red hat:openssl-config-fips0:3.5.6-0.1.hum1 · Red Hat:hummingbird:1Package registry (OSV)
red hat:openssl-debuginfo1:3.5.1-7.el10_1 · Red Hat:enterprise_linux:10.1Package registry (OSV)
red hat:openssl-debugsource1:3.5.1-7.el10_1 · Red Hat:enterprise_linux:10.1Package registry (OSV)
red hat:openssl-devel1:3.5.1-7.el10_1 · Red Hat:enterprise_linux:10.1Package registry (OSV)
red hat:openssl-devel-engine0:3.5.6-0.1.hum1 · Red Hat:hummingbird:1Package registry (OSV)
red hat:openssl-libs1:3.5.1-7.el10_1 · Red Hat:enterprise_linux:10.1Package registry (OSV)
red hat:openssl-libs-debuginfo1:3.5.1-7.el10_1 · Red Hat:enterprise_linux:10.1Package registry (OSV)
red hat:openssl-perl1:3.5.1-7.el10_1 · Red Hat:enterprise_linux:10.1Package registry (OSV)
rocky linux:openssl1:3.5.1-7.el10_1 · Rocky Linux:10Package registry (OSV)
suse:openssl-1_0_01.0.2p-150000.3.102.1 · SUSE:Linux Enterprise Module for Legacy 15 SP7Package registry (OSV)
suse:openssl-1_11.1.1w-150600.5.21.1 · SUSE:Linux Enterprise Server 15 SP6-LTSSPackage registry (OSV)
suse:openssl-1_11.1.1w-150700.11.11.1 · SUSE:Linux Enterprise Module for Basesystem 15 SP7Package registry (OSV)
suse:openssl-33.1.4-150600.5.42.1 · SUSE:Linux Enterprise Server 15 SP6-LTSSPackage registry (OSV)
suse:openssl-33.2.3-150700.5.24.1 · SUSE:Linux Enterprise Module for Basesystem 15 SP7Package registry (OSV)

+1

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-2025-694200 days apartMissing ASN1_TYPE validation in TS_RESP_verify_response() function
    30Monitor
  • CVE-2026-3179070 days apartIncorrect Failure Handling in RSA KEM RSASVE Encapsulation
    30Monitor
  • CVE-2026-227950 days apartMissing ASN1_TYPE validation in PKCS#12 parsing
    22Monitor

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).

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.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
none
Integrity
none
Availability
low · the service can be disrupted
Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality impact
None
Integrity impact
None
Availability impact
Low

Weakness class (CWE)

CWE-754 · Improper Check for Unusual or Exceptional Conditions

CVSS vector

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

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.

MITRE has no CAPEC/ATT&CK mapping for this CWE.

Change log

  1. Fix✗ → ✓

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

References

Show all references (6 more)

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

All records