Buffer overflow in Cryptography.io Cryptography
CVE-2020-36242
In the cryptography package before 3.3.2 for Python, certain sequences of update calls to symmetrically encrypt multi-GB values could result in an integer overflow and buffer overflow, as demonstrated by the Fernet class.
Vulnerability class: Integer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 9.1 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H.
EPSS exploit prediction
EPSS: 0.067 (93.9th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 94th percentile — 93.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.067 · newest: 0.067 · change: 0.000
Affected products
- Cryptography.io Cryptography
- Oracle Communications Cloud Native Core Network Function Environment — versions 1.10.0
- Fedoraproject Fedora — versions 33
Weakness classification (CWE)
Public proof-of-concept exploits
References
- github.com/pyca/cryptography/issues/5615 (Exploit, Patch, Third Party Advisory)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/… (vendor-advisory)
- www.oracle.com/security-alerts/cpuapr2022.html (Patch, Third Party Advisory)
- github.com/pyca/cryptography/compare/3.3.1...3.3.2 (Patch, Third Party Advisory)
- github.com/pyca/cryptography/blob/master/CHANGELOG.rst (Third Party Advisory, Release Notes)
- www.oracle.com/security-alerts/cpujul2022.html (Patch, Third Party Advisory)
Frequently asked questions
- What is CVE-2020-36242?
- CVE-2020-36242 is a critical-severity vulnerability in Cryptography.io Cryptography, classified under Integer Overflow or Wraparound. CVSS score: 9.1/10. Published 2021-02-07.
- How severe is CVE-2020-36242?
- Critical severity. CVSS v3 base score is 9.1 out of 10.
- Is CVE-2020-36242 known to be exploited?
- 7 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.