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Fencer Intel
high 8.2

CVE-2026-69247 json

cryptography: PKCS#7 EnvelopedData decryption exposes a Bleichenbacher oracle through distinguishable errors and timing

published 3mo ago modified 19d ago also EUVD-2026-52446 , GHSA-g6cj-pr64-35w5 , PYSEC-2026-3552

cvss
8.2
version 4.0, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.3%
EPSS 0.3% chance of exploitation in 30 days, percentile 20%
public exploits
0
none known

Summary

cryptography is a package designed to expose cryptographic primitives and recipes to Python developers. From 44.0.0 until 50.0.0, pkcs7_decrypt_der, pkcs7_decrypt_pem, and pkcs7_decrypt_smime reported the outcome of decrypting a RecipientInfo's encryptedKey in several distinguishable ways, one of which disclosed the exact length recovered from the RSA operation. The same distinction was also observable by timing. An application that decrypts attacker-supplied EnvelopedData and reflects the outcome gives the attacker a Bleichenbacher oracle against the content-encryption key. Decryption ran as RSA PKCS#1 v1.5 decrypt of encryptedKey, build an AES cipher from the result, then AES-CBC decrypt and PKCS#7 unpad. Invalid RSA padding, a valid padding with a bad key length, a correct length with a wrong key, and the real key each failed or succeeded differently. Case 1 is reachable only where the linked library lacks implicit rejection: OpenSSL 3.0 and 3.1, LibreSSL, and BoringSSL. Exploitation requires a service that auto-decrypts untrusted EnvelopedData matching the victim certificate and answers adaptively at high volume, such as an S/MIME gateway or mail filter. This issue is fixed in 50.0.0.

Patch / fix

  • pypi cryptography 50.0.0
  • cryptography.io cryptography 50.0.0
  • cryptography_project cryptography 50.0.0
  • python-cryptography_project python-cryptography 50.0.0
  • python-cryptography Debian 14 49.0.0-2

debian advisories DEBIAN-CVE-2026-69247

  • python-cryptography Ubuntu 26.04 LTS 46.0.5-1ubuntu2.2

ubuntu advisories UBUNTU-CVE-2026-69247

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • python-cryptography hummingbird 1 50.0.0-1.hum1
  • python3-cryptography hummingbird 1 50.0.0-1.hum1

red hat advisories RHSA-2026:55543

  • python-cryptography SLES 16.0, Linux Micro 6.2, SLES for SAP applications 16.0 44.0.3-160000.5.1

suse advisories SUSE-SU-2026:23404-1SUSE-SU-2026:23570-1

  • python-cryptography openSUSE Leap 16.0 44.0.3-160000.5.1
  • python-cryptography openSUSE Tumbleweed 50.0.0-1.1

opensuse advisories openSUSE-SU-2026:21685-1openSUSE-SU-2026:11468-1

Is CVE-2026-69247 in your dependencies? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.

Check with Fencer

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-69247 updated cvss 5.9

python-cryptography: python-cryptography: PKCS#7 EnvelopedData decryption exposes a Bleichenbacher oracle through distinguishable errors and timing

  • Red Hat Ansible Automation Platform 2 python-cryptography 46.0.7-3.el10ap, python3.12-cryptography 46.0.5-2.el9ap Red Hat Enterprise Linux 9 python3.14-cryptography, python3.14-cryptography 45.0.4-4.el10_2.5 Red Hat Enterprise Linux 10 python-cryptography 46.0.7-3.el10ap, python3.14-cryptography 45.0.4-4.el10_2.5 Red Hat OpenShift AI (RHOAI) rhoai/odh-mlflow-rhel9 Red Hat Satellite 6 python3-cryptography, python-cryptography 46.0.7-3.el10ap, python3.12-cryptography 46.0.5-2.el9ap
    affected: workaround, no fix available “Fix deferred”
  • Red Hat AI Inference Server 3.4 rhaii/vllm-cpu-rhel9 1790075793, rhaii/vllm-cuda-rhel9 1790090131, rhaii/vllm-rocm-rhel9 1790109620, rhaii/vllm-spyre-rhel9 1790076141
    fixed: vendor fix RHSA-2026:70965
  • Red Hat Hardened Images python-cryptography 50.0.0-1.hum1, python3-cryptography 50.0.0-1.hum1
    fixed: vendor fix RHSA-2026:55543
  • Red Hat Ansible Automation Platform 2 python3x-cryptography 42.0.5-1.el8ap, python3.11-cryptography 42.0.5-1.el8ap Red Hat Enterprise Linux 8 python3-cryptography, python-cryptography 46.0.7-3.el10ap, python3.12-cryptography 46.0.5-2.el9ap Red Hat Enterprise Linux 9 python3-cryptography, python3.12-cryptography, python-cryptography 46.0.7-3.el10ap, python3.12-cryptography 46.0.5-2.el9ap
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
3mo ago

Exploit prediction

0.27% chance of exploitation in the next 30 days, higher than 20% of all scored CVEs (FIRST EPSS, 2026-11-11).

CVSS scores

assigned by version score vector
CNA 4.0 8.2 CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N
CNA 4.0 8.2 CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Affected packages

ecosystem package affected fixed in
pypi cryptography
>=44.0.0, <50.0.0
50.0.0

Affected products

  • pyca cryptography

Classification

Weakness
  • CWE-208 Observable Timing Discrepancy
  • CWE-209 Generation of Error Message Containing Sensitive Information

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

The maintainers of pyca/cryptography published their own advisory on GitHub. Reviewed sources take precedence over it.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.