CVE-2023-49083: cryptography vulnerable to NULL-dereference when loading PKCS7 certificates
Noroxi assessment
Priority: Monitor (action score 30/100)
- 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: 0.98% (FIRST EPSS); higher than 62.3% of all records.
- 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.
- Fixed version: pyca cryptography 41.0.6.
Low priority for now. Upgrade to pyca cryptography 41.0.6 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
cryptography is a package designed to expose cryptographic primitives and recipes to Python developers. Calling `load_pem_pkcs7_certificates` or `load_der_pkcs7_certificates` could lead to a NULL-pointer dereference and segfault. Exploitation of this vulnerability poses a serious risk of Denial of Service (DoS) for any application attempting to deserialize a PKCS7 blob/certificate. The consequences extend to potential disruptions in system availability and stability. This vulnerability has been patched in version 41.0.6.
- BDU:2024-02534
- GHSA-jfhm-5ghh-2f97
- ALSA-2024:2337
- ALSA-2024:3105
- ALSA-2025:14553
- ALSA-2025:15874
- DLA-3922-1
- openSUSE-SU-2024:13472-1
- openSUSE-SU-2026:11468-1
- PYSEC-2023-254
- RHSA-2024:10965
- RHSA-2024:1640
- RHSA-2024:1878
- RHSA-2024:2337
- RHSA-2024:3105
- RHSA-2024:3781
- RHSA-2025:13098
- RHSA-2025:13100
- RHSA-2025:13101
- RHSA-2025:13102
- Published
- Nov 29, 2023
- Updated
- Jun 17, 2026
- EPSS
- 0.9% · 62th percentile
- CWE
- CWE-476
Report tools
Action score
30
Monitor
Low priority for now.
- CVSS
- 30 / 40 · 7.5 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 0.9%
CISA SSVC decision
- Exploitation
- proof of concept
- Automatable
- no
- Technical impact
- partial
Vulnrichment: CISA's decision-tree inputs.
CNA vs NVD score
- NVD
- 7.5
- CNA · GitHub_M
- 5.9
- 1.6 point gap
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.
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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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.
We use this product, ask for helpAffected 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.
| Vendor | Product | CPE |
|---|---|---|
| cryptography.io | cryptography | cpe:2.3:a:cryptography.io:cryptography |
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- cryptography.io cryptography3.1 and later · before 41.0.6
Versions reported by the vendor
Affected version ranges reported by the assigning authority (GitHub_M). Independent of NVD's CPE analysis and usually ahead of it.
pyca cryptography
- >= 3.1, < 41.0.6affected
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| AlmaLinux:8 | python3-cryptography | before 3.2.1-8.el8_10 | 3.2.1-8.el8_10 |
| AlmaLinux:8 | python3.11-cryptography | before 37.0.2-6.el8 | 37.0.2-6.el8 |
| AlmaLinux:9 | python3-cryptography | before 36.0.1-5.el9_6 | 36.0.1-5.el9_6 |
| AlmaLinux:9 | python3.11-cryptography | before 37.0.2-6.el9 | 37.0.2-6.el9 |
| Debian:11 | python-cryptography | before 3.3.2-1+deb11u1 | 3.3.2-1+deb11u1 |
| Debian:12 | python-cryptography | before 38.0.4-3+deb12u1 | 38.0.4-3+deb12u1 |
| Debian:13 | python-cryptography | before 41.0.7-1 | 41.0.7-1 |
| openSUSE:Leap 15.4 | python-cryptography | before 41.0.3-150400.16.12.1 | 41.0.3-150400.16.12.1 |
| openSUSE:Leap Micro 5.3 | python3-cryptography | before 3.3.2-150400.23.1 | 3.3.2-150400.23.1 |
| openSUSE:Tumbleweed | python-cryptography | before 41.0.7-1.1 | 41.0.7-1.1 |
| openSUSE:Tumbleweed | python-cryptography | before 50.0.0-1.1 | 50.0.0-1.1 |
| PyPI | cryptography | from 3.1 · before 41.0.6 | 41.0.6 |
| Red Hat:ansible_automation_platform_developer:2.4::el8 | python39-black | before 0:22.8.0-2.el8ap | 0:22.8.0-2.el8ap |
| Red Hat:ansible_automation_platform_developer:2.4::el8 | python39-cryptography | before 0:42.0.5-1.el8ap | 0:42.0.5-1.el8ap |
| Red Hat:ansible_automation_platform_developer:2.4::el8 | python39-cryptography-debuginfo | before 0:42.0.5-1.el8ap | 0:42.0.5-1.el8ap |
| Red Hat:ansible_automation_platform_developer:2.4::el8 | python39-idna | before 0:3.7-1.el8ap | 0:3.7-1.el8ap |
| Red Hat:ansible_automation_platform_developer:2.4::el8 | python39-jinja2 | before 0:3.1.4-1.el8ap | 0:3.1.4-1.el8ap |
| Red Hat:ansible_automation_platform_developer:2.4::el8 | python39-requests | before 0:2.32.2-1.el8ap | 0:2.32.2-1.el8ap |
| Red Hat:ansible_automation_platform_developer:2.4::el8 | python3x-black | before 0:22.8.0-2.el8ap | 0:22.8.0-2.el8ap |
| Red Hat:ansible_automation_platform_developer:2.4::el8 | python3x-cryptography | before 0:42.0.5-1.el8ap | 0:42.0.5-1.el8ap |
| Red Hat:ansible_automation_platform_developer:2.4::el8 | python3x-cryptography-debugsource | before 0:42.0.5-1.el8ap | 0:42.0.5-1.el8ap |
| Red Hat:ansible_automation_platform_developer:2.4::el8 | python3x-idna | before 0:3.7-1.el8ap | 0:3.7-1.el8ap |
| Red Hat:ansible_automation_platform_developer:2.4::el8 | python3x-jinja2 | before 0:3.1.4-1.el8ap | 0:3.1.4-1.el8ap |
| Red Hat:ansible_automation_platform_developer:2.4::el8 | python3x-requests | before 0:2.32.2-1.el8ap | 0:2.32.2-1.el8ap |
+96
Same product
cryptography.io: all recordsOther highest-scoring records for the same primary product.
- CVE-2020-36242In the cryptography package before 3.3.2 for Python, certain sequences of update calls to symmetrically encrypt multi-GB values could result38Monitor
- CVE-2026-26007cryptography Subgroup Attack Due to Missing Subgroup Validation for SECT Curves32Monitor
- CVE-2016-9243HKDF in cryptography before 1.5.2 returns an empty byte-string if used with a length less than algorithm.digest_size.31Monitor
Published before and after this one in the same product
- ← EarlierCVE-2023-23931Feb 7, 2023 · Cipher.update_into can corrupt memory in pyca cryptography26Monitor
- ← EarlierCVE-2023-38325Jul 14, 2023 · The cryptography package before 41.0.2 for Python mishandles SSH certificates that have critical options.30Monitor
- Later →CVE-2024-26130Feb 21, 2024 · cryptography NULL pointer deference with pkcs12.serialize_key_and_certificates when called with a non-matching certificate and private key and an hmac_hash over30Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| pyca cryptography | 41.0.6 · description | Vendor (CNA) |
| almalinux:python3-cryptography | 3.2.1-8.el8_10 · AlmaLinux:8 | Package registry (OSV) |
| almalinux:python3.11-cryptography | 37.0.2-6.el9 · AlmaLinux:9 | Package registry (OSV) |
| debian:python-cryptography | 38.0.4-3+deb12u1 · Debian:12 | Package registry (OSV) |
| opensuse:python-cryptography | 41.0.3-150400.16.12.1 · openSUSE:Leap 15.4 | Package registry (OSV) |
| opensuse:python3-cryptography | 3.3.2-150400.23.1 · openSUSE:Leap Micro 5.3 | Package registry (OSV) |
| PyPI:cryptography | 41.0.6 | Package registry (OSV) |
| red hat:automation-controller-venv-tower | 0:4.5.5-2.el8ap · Red Hat:ansible_automation_platform:2.4::el8 | Package registry (OSV) |
| red hat:python-aiohttp | 0:3.9.3-1.el9ap · Red Hat:ansible_automation_platform:2.4::el9 | Package registry (OSV) |
| red hat:python-aiohttp-debugsource | 0:3.9.3-1.el9ap · Red Hat:ansible_automation_platform:2.4::el9 | Package registry (OSV) |
| red hat:python3.11-cryptography | 0:37.0.2-5.el8_8.1 · Red Hat:rhel_eus:8.8::appstream | Package registry (OSV) |
| red hat:python3.11-cryptography-debuginfo | 0:37.0.2-5.el8_8.1 · Red Hat:rhel_eus:8.8::appstream | Package registry (OSV) |
| red hat:python3.11-cryptography-debugsource | 0:37.0.2-5.el8_8.1 · Red Hat:rhel_eus:8.8::appstream | Package registry (OSV) |
| red hat:python39-aiohttp | 0:3.9.3-1.el8ap · Red Hat:ansible_automation_platform:2.4::el8 | Package registry (OSV) |
| red hat:python39-aiohttp-debuginfo | 0:3.9.3-1.el8ap · Red Hat:ansible_automation_platform:2.4::el8 | Package registry (OSV) |
| red hat:python3x-aiohttp | 0:3.9.3-1.el8ap · Red Hat:ansible_automation_platform:2.4::el8 | Package registry (OSV) |
| red hat:python3x-aiohttp-debugsource | 0:3.9.3-1.el8ap · Red Hat:ansible_automation_platform:2.4::el8 | Package registry (OSV) |
| red hat:receptor | 0:1.4.5-1.el8ap · Red Hat:ansible_automation_platform_developer:2.4::el8 | Package registry (OSV) |
| red hat:receptorctl | 0:1.4.5-1.el8ap · Red Hat:ansible_automation_platform_developer:2.4::el8 | Package registry (OSV) |
| rocky linux:python-cryptography | 0:3.2.1-8.el8_10 · Rocky Linux:8 | Package registry (OSV) |
| rocky linux:python3.11-cryptography | 0:37.0.2-6.el9 · Rocky Linux:9 | Package registry (OSV) |
| suse:python-cryptography | 41.0.3-150400.16.12.1 · SUSE:Linux Enterprise Module for Python 3 15 SP4 | Package registry (OSV) |
| suse:python3-cryptography | 3.3.2-150400.23.1 · SUSE:Linux Enterprise Micro 5.3 | Package 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 researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
No credits in the CNA record.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
- CVE-2024-2613084 days apartcryptography NULL pointer deference with pkcs12.serialize_key_and_certificates when called with a non-matching certificate and private key and an hmac_hash over30Monitor
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
- high · 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
- High
Weakness class (CWE)
CWE-476 · NULL Pointer DereferenceCVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
nvd-primary
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
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
Show all references (3 more)Show less
Vendor advisories and official records. Exploit/PoC links are deliberately left out.