Vulnerability in OpenSSL

CVE-2018-0739

Constructed ASN.1 types with a recursive definition (such as can be found in PKCS7) could eventually exceed the stack given malicious input with excessive recursion. This could result in a Denial Of Service attack. There are no such structures used within SSL/TLS that come from untrusted sources so this is considered safe. Fixed in OpenSSL 1.1.0h (Affected 1.1.0-1.1.0g). Fixed in OpenSSL 1.0.2o (Affected 1.0.2b-1.0.2n).

Published · last modified .

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.186 (97.2th percentile), scored .

Moderate probability of exploitation in the next 30 days — watch for active exploitation reports. 97th percentile — 97.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2018-0739: held from 0.189 to 0.186.

EPSS over last 30 days · oldest: 0.189 · newest: 0.186 · change: -0.003

Affected products

  • OpenSSL — versions Fixed in OpenSSL 1.0.2o (Affected 1.0.2b-1.0.2n), Fixed in OpenSSL 1.1.0h (Affected 1.1.0-1.1.0g)
  • Canonical Ubuntu Linux — versions 14.04, 16.04, 17.10
  • Debian Linux — versions 7.0, 8.0, 9.0

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2018-0739?
CVE-2018-0739 is a medium-severity vulnerability in OpenSSL, classified under Uncontrolled Recursion. CVSS score: 6.5/10. Published 2018-03-27.
How severe is CVE-2018-0739?
Medium severity. CVSS v3 base score is 6.5 out of 10.
Is CVE-2018-0739 known to be exploited?
3 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.